* [PATCH v6] rtc: rewrite DS1302 using SPI
@ 2016-02-22 1:41 ` Sergei Ianovich
0 siblings, 0 replies; 38+ messages in thread
From: Sergei Ianovich @ 2016-02-22 1:41 UTC (permalink / raw)
To: linux-kernel
Cc: Sergei Ianovich, Alexandre Belloni, Rob Herring, Rob Herring,
Pawel Moll, Mark Rutland, Ian Campbell, Kumar Gala,
Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK SUBSYSTEM
DS1302 is half-duplex SPI device. The driver respects this fact now.
Pin configurations should be implemented using SPI subsystem.
Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
CC: Alexandre Belloni <alexandre.belloni@free-electrons.com>
CC: Rob Herring <robh@kernel.org>
---
v5..v6
* rewrite the driver as an SPI slave device
* use "maxim" for vendor name per Kconfig
* stop touching device RAM in device presence test
* only return time from device if valid
* use burst mode for reading/writing time
* droppped charging control. I cannot test it, and it looks broken
v4..v5
* drop THIS_MODULE from struct platform driver
* use "dallas" for vendor name per vendor-prefixes.txt
v3..v4
* move DTS bindings to a different patch
v2..v3
* use usleep_range instead of custom nsleep
* number change (07/16 -> 09/21)
v0..v2
* use device tree
* use devm helpers where possible
.../devicetree/bindings/rtc/rtc-ds1302.txt | 46 +++
drivers/rtc/Kconfig | 15 +-
drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
3 files changed, 212 insertions(+), 197 deletions(-)
create mode 100644 Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
diff --git a/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt b/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
new file mode 100644
index 0000000..b6c0973
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
@@ -0,0 +1,46 @@
+* Maxim/Dallas Semiconductor DS-1302 RTC
+
+Simple device which could be used to store date/time between reboots.
+
+The device uses the standard MicroWire half-duplex transfer timing.
+Master output is set on low clock and sensed by the RTC on the rising
+edge. Master input is set by the RTC on the trailing edge and is sensed
+by the master on low clock.
+
+Required properties:
+
+- compatible : Should be "maxim,rtc-ds1302"
+
+Required SPI properties:
+
+- reg : Should be address of the device chip select within
+ the controller.
+
+- spi-max-frequency : DS-1302 has 500 kHz if powered at 2.2V,
+ and 2MHz if powered at 5V.
+
+- spi-3wire : The device has a shared signal IN/OUT line.
+
+- spi-lsb-first : DS-1302 requires least significant bit first
+ transfers.
+
+- spi-cs-high: DS-1302 has active high chip select line. This is
+ required unless inverted in hardware.
+
+Example:
+
+spi0@901c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "icpdas,spi-lp8841-rtc";
+ reg = <0x901c 0x1>;
+
+ rtc@0 {
+ compatible = "maxim,rtc-ds1302";
+ reg = <0>;
+ spi-max-frequency = <500000>;
+ spi-3wire;
+ spi-lsb-first;
+ spi-cs-high;
+ };
+};
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 2a52424..2e54aad 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -646,6 +646,15 @@ config RTC_DRV_M41T94
This driver can also be built as a module. If so, the module
will be called rtc-m41t94.
+config RTC_DRV_DS1302
+ tristate "Dallas/Maxim DS1302"
+ depends on SPI
+ help
+ If you say yes here you get support for the Dallas DS1302 RTC chips.
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-ds1302.
+
config RTC_DRV_DS1305
tristate "Dallas/Maxim DS1305/DS1306"
help
@@ -811,12 +820,6 @@ config RTC_DRV_DS1286
help
If you say yes here you get support for the Dallas DS1286 RTC chips.
-config RTC_DRV_DS1302
- tristate "Dallas DS1302"
- depends on SH_SECUREEDGE5410
- help
- If you say yes here you get support for the Dallas DS1302 RTC chips.
-
config RTC_DRV_DS1511
tristate "Dallas DS1511"
depends on HAS_IOMEM
diff --git a/drivers/rtc/rtc-ds1302.c b/drivers/rtc/rtc-ds1302.c
index 6bef7a5..89a210b 100644
--- a/drivers/rtc/rtc-ds1302.c
+++ b/drivers/rtc/rtc-ds1302.c
@@ -9,16 +9,17 @@
* this archive for more details.
*/
+#include <linux/bcd.h>
#include <linux/init.h>
-#include <linux/module.h>
+#include <linux/io.h>
#include <linux/kernel.h>
-#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/of.h>
#include <linux/rtc.h>
-#include <linux/io.h>
-#include <linux/bcd.h>
+#include <linux/spi/spi.h>
#define DRV_NAME "rtc-ds1302"
-#define DRV_VERSION "0.1.1"
+#define DRV_VERSION "1.0.0"
#define RTC_CMD_READ 0x81 /* Read command */
#define RTC_CMD_WRITE 0x80 /* Write command */
@@ -28,6 +29,8 @@
#define RTC_ADDR_RAM0 0x20 /* Address of RAM0 */
#define RTC_ADDR_TCR 0x08 /* Address of trickle charge register */
+#define RTC_CLCK_BURST 0x1F /* Address of clock burst */
+#define RTC_CLCK_LEN 0x08 /* Size of clock burst */
#define RTC_ADDR_CTRL 0x07 /* Address of control register */
#define RTC_ADDR_YEAR 0x06 /* Address of year register */
#define RTC_ADDR_DAY 0x05 /* Address of day of week register */
@@ -37,217 +40,180 @@
#define RTC_ADDR_MIN 0x01 /* Address of minute register */
#define RTC_ADDR_SEC 0x00 /* Address of second register */
-#ifdef CONFIG_SH_SECUREEDGE5410
-#include <asm/rtc.h>
-#include <mach/secureedge5410.h>
-
-#define RTC_RESET 0x1000
-#define RTC_IODATA 0x0800
-#define RTC_SCLK 0x0400
-
-#define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00)
-#define get_dp() SECUREEDGE_READ_IOPORT()
-#define ds1302_set_tx()
-#define ds1302_set_rx()
-
-static inline int ds1302_hw_init(void)
+static int ds1302_rtc_set_time(struct device *dev, struct rtc_time *time)
{
- return 0;
+ struct spi_device *spi = dev_get_drvdata(dev);
+ u8 buf[1 + RTC_CLCK_LEN];
+ u8 *bp = buf;
+ int status;
+
+ /* Enable writing */
+ bp = buf;
+ *bp++ = RTC_ADDR_CTRL << 1 | RTC_CMD_WRITE;
+ *bp++ = RTC_CMD_WRITE_ENABLE;
+
+ status = spi_write_then_read(spi, buf, 2,
+ NULL, 0);
+ if (!status)
+ return status;
+
+ /* Write registers starting at the first time/date address. */
+ bp = buf;
+ *bp++ = RTC_CLCK_BURST << 1 | RTC_CMD_WRITE;
+
+ *bp++ = bin2bcd(time->tm_sec);
+ *bp++ = bin2bcd(time->tm_min);
+ *bp++ = bin2bcd(time->tm_hour);
+ *bp++ = bin2bcd(time->tm_mday);
+ *bp++ = bin2bcd(time->tm_mon + 1);
+ *bp++ = time->tm_wday;
+ *bp++ = bin2bcd(time->tm_year % 100);
+ *bp++ = RTC_CMD_WRITE_DISABLE;
+
+ /* use write-then-read since dma from stack is nonportable */
+ return spi_write_then_read(spi, buf, sizeof(buf),
+ NULL, 0);
}
-static inline void ds1302_reset(void)
+static int ds1302_rtc_get_time(struct device *dev, struct rtc_time *time)
{
- set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK));
+ struct spi_device *spi = dev_get_drvdata(dev);
+ u8 addr = RTC_CLCK_BURST << 1 | RTC_CMD_READ;
+ u8 buf[RTC_CLCK_LEN - 1];
+ int status;
+
+ /* Use write-then-read to get all the date/time registers
+ * since dma from stack is nonportable
+ */
+ status = spi_write_then_read(spi, &addr, sizeof(addr),
+ buf, sizeof(buf));
+ if (status < 0)
+ return status;
+
+ /* Decode the registers */
+ time->tm_sec = bcd2bin(buf[RTC_ADDR_SEC]);
+ time->tm_min = bcd2bin(buf[RTC_ADDR_MIN]);
+ time->tm_hour = bcd2bin(buf[RTC_ADDR_HOUR]);
+ time->tm_wday = buf[RTC_ADDR_DAY] - 1;
+ time->tm_mday = bcd2bin(buf[RTC_ADDR_DATE]);
+ time->tm_mon = bcd2bin(buf[RTC_ADDR_MON]) - 1;
+ time->tm_year = bcd2bin(buf[RTC_ADDR_YEAR]) + 100;
+
+ /* Time may not be set */
+ return rtc_valid_tm(time);
}
-static inline void ds1302_clock(void)
-{
- set_dp(get_dp() | RTC_SCLK); /* clock high */
- set_dp(get_dp() & ~RTC_SCLK); /* clock low */
-}
-
-static inline void ds1302_start(void)
-{
- set_dp(get_dp() | RTC_RESET);
-}
-
-static inline void ds1302_stop(void)
-{
- set_dp(get_dp() & ~RTC_RESET);
-}
-
-static inline void ds1302_txbit(int bit)
-{
- set_dp((get_dp() & ~RTC_IODATA) | (bit ? RTC_IODATA : 0));
-}
-
-static inline int ds1302_rxbit(void)
-{
- return !!(get_dp() & RTC_IODATA);
-}
-
-#else
-#error "Add support for your platform"
-#endif
+static struct rtc_class_ops ds1302_rtc_ops = {
+ .read_time = ds1302_rtc_get_time,
+ .set_time = ds1302_rtc_set_time,
+};
-static void ds1302_sendbits(unsigned int val)
+static int ds1302_probe(struct spi_device *spi)
{
- int i;
-
- ds1302_set_tx();
-
- for (i = 8; (i); i--, val >>= 1) {
- ds1302_txbit(val & 0x1);
- ds1302_clock();
+ struct rtc_device *rtc;
+ u8 addr;
+ u8 buf[4];
+ u8 *bp = buf;
+ int status;
+
+ /* Sanity check board setup data. This may be hooked up
+ * in 3wire mode, but we don't care. Note that unless
+ * there's an inverter in place, this needs SPI_CS_HIGH!
+ */
+ if (spi->bits_per_word && (spi->bits_per_word != 8)) {
+ dev_err(&spi->dev, "bad word length\n");
+ return -EINVAL;
+ } else if (spi->max_speed_hz > 2000000) {
+ dev_err(&spi->dev, "speed is too high\n");
+ return -EINVAL;
+ } else if (spi->mode & SPI_CPHA) {
+ dev_err(&spi->dev, "bad mode\n");
+ return -EINVAL;
}
-}
-
-static unsigned int ds1302_recvbits(void)
-{
- unsigned int val;
- int i;
-
- ds1302_set_rx();
- for (i = 0, val = 0; (i < 8); i++) {
- val |= (ds1302_rxbit() << i);
- ds1302_clock();
+ addr = RTC_ADDR_CTRL << 1 | RTC_CMD_READ;
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register read error %d\n",
+ status);
+ return status;
}
- return val;
-}
-
-static unsigned int ds1302_readbyte(unsigned int addr)
-{
- unsigned int val;
-
- ds1302_reset();
-
- ds1302_start();
- ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_READ);
- val = ds1302_recvbits();
- ds1302_stop();
-
- return val;
-}
-
-static void ds1302_writebyte(unsigned int addr, unsigned int val)
-{
- ds1302_reset();
-
- ds1302_start();
- ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_WRITE);
- ds1302_sendbits(val);
- ds1302_stop();
-}
-
-static int ds1302_rtc_read_time(struct device *dev, struct rtc_time *tm)
-{
- tm->tm_sec = bcd2bin(ds1302_readbyte(RTC_ADDR_SEC));
- tm->tm_min = bcd2bin(ds1302_readbyte(RTC_ADDR_MIN));
- tm->tm_hour = bcd2bin(ds1302_readbyte(RTC_ADDR_HOUR));
- tm->tm_wday = bcd2bin(ds1302_readbyte(RTC_ADDR_DAY));
- tm->tm_mday = bcd2bin(ds1302_readbyte(RTC_ADDR_DATE));
- tm->tm_mon = bcd2bin(ds1302_readbyte(RTC_ADDR_MON)) - 1;
- tm->tm_year = bcd2bin(ds1302_readbyte(RTC_ADDR_YEAR));
-
- if (tm->tm_year < 70)
- tm->tm_year += 100;
-
- dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
- "mday=%d, mon=%d, year=%d, wday=%d\n",
- __func__,
- tm->tm_sec, tm->tm_min, tm->tm_hour,
- tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
-
- return rtc_valid_tm(tm);
-}
-
-static int ds1302_rtc_set_time(struct device *dev, struct rtc_time *tm)
-{
- ds1302_writebyte(RTC_ADDR_CTRL, RTC_CMD_WRITE_ENABLE);
- /* Stop RTC */
- ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) | 0x80);
-
- ds1302_writebyte(RTC_ADDR_SEC, bin2bcd(tm->tm_sec));
- ds1302_writebyte(RTC_ADDR_MIN, bin2bcd(tm->tm_min));
- ds1302_writebyte(RTC_ADDR_HOUR, bin2bcd(tm->tm_hour));
- ds1302_writebyte(RTC_ADDR_DAY, bin2bcd(tm->tm_wday));
- ds1302_writebyte(RTC_ADDR_DATE, bin2bcd(tm->tm_mday));
- ds1302_writebyte(RTC_ADDR_MON, bin2bcd(tm->tm_mon + 1));
- ds1302_writebyte(RTC_ADDR_YEAR, bin2bcd(tm->tm_year % 100));
+ if ((buf[0] & ~RTC_CMD_WRITE_DISABLE) != 0) {
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register read error %d\n",
+ status);
+ return status;
+ }
+
+ if ((buf[0] & ~RTC_CMD_WRITE_DISABLE) != 0) {
+ dev_err(&spi->dev, "junk in control register\n");
+ return -ENODEV;
+ }
+ }
+ if (buf[0] == 0) {
+ bp = buf;
+ *bp++ = RTC_ADDR_CTRL << 1 | RTC_CMD_WRITE;
+ *bp++ = RTC_CMD_WRITE_DISABLE;
+
+ status = spi_write_then_read(spi, buf, 2, NULL, 0);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register write error %d\n",
+ status);
+ return status;
+ }
+
+ addr = RTC_ADDR_CTRL << 1 | RTC_CMD_READ;
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev,
+ "error %d reading control register\n",
+ status);
+ return status;
+ }
+
+ if (buf[0] != RTC_CMD_WRITE_DISABLE) {
+ dev_err(&spi->dev, "failed to detect chip\n");
+ return -ENODEV;
+ }
+ }
- /* Start RTC */
- ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) & ~0x80);
+ spi_set_drvdata(spi, spi);
- ds1302_writebyte(RTC_ADDR_CTRL, RTC_CMD_WRITE_DISABLE);
+ rtc = devm_rtc_device_register(&spi->dev, "ds1302",
+ &ds1302_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc)) {
+ status = PTR_ERR(rtc);
+ dev_err(&spi->dev, "error %d registering rtc\n", status);
+ return status;
+ }
return 0;
}
-static int ds1302_rtc_ioctl(struct device *dev, unsigned int cmd,
- unsigned long arg)
+static int ds1302_remove(struct spi_device *spi)
{
- switch (cmd) {
-#ifdef RTC_SET_CHARGE
- case RTC_SET_CHARGE:
- {
- int tcs_val;
-
- if (copy_from_user(&tcs_val, (int __user *)arg, sizeof(int)))
- return -EFAULT;
-
- ds1302_writebyte(RTC_ADDR_TCR, (0xa0 | tcs_val * 0xf));
- return 0;
- }
-#endif
- }
-
- return -ENOIOCTLCMD;
+ spi_set_drvdata(spi, NULL);
+ return 0;
}
-static struct rtc_class_ops ds1302_rtc_ops = {
- .read_time = ds1302_rtc_read_time,
- .set_time = ds1302_rtc_set_time,
- .ioctl = ds1302_rtc_ioctl,
+#ifdef CONFIG_OF
+static const struct of_device_id ds1302_dt_ids[] = {
+ { .compatible = "maxim,rtc-ds1302", },
+ { /* sentinel */ }
};
+MODULE_DEVICE_TABLE(of, ds1302_dt_ids);
+#endif
-static int __init ds1302_rtc_probe(struct platform_device *pdev)
-{
- struct rtc_device *rtc;
-
- if (ds1302_hw_init()) {
- dev_err(&pdev->dev, "Failed to init communication channel");
- return -EINVAL;
- }
-
- /* Reset */
- ds1302_reset();
-
- /* Write a magic value to the DS1302 RAM, and see if it sticks. */
- ds1302_writebyte(RTC_ADDR_RAM0, 0x42);
- if (ds1302_readbyte(RTC_ADDR_RAM0) != 0x42) {
- dev_err(&pdev->dev, "Failed to probe");
- return -ENODEV;
- }
-
- rtc = devm_rtc_device_register(&pdev->dev, "ds1302",
- &ds1302_rtc_ops, THIS_MODULE);
- if (IS_ERR(rtc))
- return PTR_ERR(rtc);
-
- platform_set_drvdata(pdev, rtc);
-
- return 0;
-}
-
-static struct platform_driver ds1302_platform_driver = {
- .driver = {
- .name = DRV_NAME,
- },
+static struct spi_driver ds1302_driver = {
+ .driver.name = "rtc-ds1302",
+ .driver.of_match_table = of_match_ptr(ds1302_dt_ids),
+ .probe = ds1302_probe,
+ .remove = ds1302_remove,
};
-module_platform_driver_probe(ds1302_platform_driver, ds1302_rtc_probe);
+module_spi_driver(ds1302_driver);
MODULE_DESCRIPTION("Dallas DS1302 RTC driver");
MODULE_VERSION(DRV_VERSION);
--
2.6.3
^ permalink raw reply related [flat|nested] 38+ messages in thread* [rtc-linux] [PATCH v6] rtc: rewrite DS1302 using SPI
@ 2016-02-22 1:41 ` Sergei Ianovich
0 siblings, 0 replies; 38+ messages in thread
From: Sergei Ianovich @ 2016-02-22 1:41 UTC (permalink / raw)
To: linux-kernel
Cc: Sergei Ianovich, Alexandre Belloni, Rob Herring, Rob Herring,
Pawel Moll, Mark Rutland, Ian Campbell, Kumar Gala,
Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK SUBSYSTEM
DS1302 is half-duplex SPI device. The driver respects this fact now.
Pin configurations should be implemented using SPI subsystem.
Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
CC: Alexandre Belloni <alexandre.belloni@free-electrons.com>
CC: Rob Herring <robh@kernel.org>
---
v5..v6
* rewrite the driver as an SPI slave device
* use "maxim" for vendor name per Kconfig
* stop touching device RAM in device presence test
* only return time from device if valid
* use burst mode for reading/writing time
* droppped charging control. I cannot test it, and it looks broken
v4..v5
* drop THIS_MODULE from struct platform driver
* use "dallas" for vendor name per vendor-prefixes.txt
v3..v4
* move DTS bindings to a different patch
v2..v3
* use usleep_range instead of custom nsleep
* number change (07/16 -> 09/21)
v0..v2
* use device tree
* use devm helpers where possible
.../devicetree/bindings/rtc/rtc-ds1302.txt | 46 +++
drivers/rtc/Kconfig | 15 +-
drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
3 files changed, 212 insertions(+), 197 deletions(-)
create mode 100644 Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
diff --git a/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt b/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
new file mode 100644
index 0000000..b6c0973
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
@@ -0,0 +1,46 @@
+* Maxim/Dallas Semiconductor DS-1302 RTC
+
+Simple device which could be used to store date/time between reboots.
+
+The device uses the standard MicroWire half-duplex transfer timing.
+Master output is set on low clock and sensed by the RTC on the rising
+edge. Master input is set by the RTC on the trailing edge and is sensed
+by the master on low clock.
+
+Required properties:
+
+- compatible : Should be "maxim,rtc-ds1302"
+
+Required SPI properties:
+
+- reg : Should be address of the device chip select within
+ the controller.
+
+- spi-max-frequency : DS-1302 has 500 kHz if powered at 2.2V,
+ and 2MHz if powered at 5V.
+
+- spi-3wire : The device has a shared signal IN/OUT line.
+
+- spi-lsb-first : DS-1302 requires least significant bit first
+ transfers.
+
+- spi-cs-high: DS-1302 has active high chip select line. This is
+ required unless inverted in hardware.
+
+Example:
+
+spi0@901c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "icpdas,spi-lp8841-rtc";
+ reg = <0x901c 0x1>;
+
+ rtc@0 {
+ compatible = "maxim,rtc-ds1302";
+ reg = <0>;
+ spi-max-frequency = <500000>;
+ spi-3wire;
+ spi-lsb-first;
+ spi-cs-high;
+ };
+};
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 2a52424..2e54aad 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -646,6 +646,15 @@ config RTC_DRV_M41T94
This driver can also be built as a module. If so, the module
will be called rtc-m41t94.
+config RTC_DRV_DS1302
+ tristate "Dallas/Maxim DS1302"
+ depends on SPI
+ help
+ If you say yes here you get support for the Dallas DS1302 RTC chips.
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-ds1302.
+
config RTC_DRV_DS1305
tristate "Dallas/Maxim DS1305/DS1306"
help
@@ -811,12 +820,6 @@ config RTC_DRV_DS1286
help
If you say yes here you get support for the Dallas DS1286 RTC chips.
-config RTC_DRV_DS1302
- tristate "Dallas DS1302"
- depends on SH_SECUREEDGE5410
- help
- If you say yes here you get support for the Dallas DS1302 RTC chips.
-
config RTC_DRV_DS1511
tristate "Dallas DS1511"
depends on HAS_IOMEM
diff --git a/drivers/rtc/rtc-ds1302.c b/drivers/rtc/rtc-ds1302.c
index 6bef7a5..89a210b 100644
--- a/drivers/rtc/rtc-ds1302.c
+++ b/drivers/rtc/rtc-ds1302.c
@@ -9,16 +9,17 @@
* this archive for more details.
*/
+#include <linux/bcd.h>
#include <linux/init.h>
-#include <linux/module.h>
+#include <linux/io.h>
#include <linux/kernel.h>
-#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/of.h>
#include <linux/rtc.h>
-#include <linux/io.h>
-#include <linux/bcd.h>
+#include <linux/spi/spi.h>
#define DRV_NAME "rtc-ds1302"
-#define DRV_VERSION "0.1.1"
+#define DRV_VERSION "1.0.0"
#define RTC_CMD_READ 0x81 /* Read command */
#define RTC_CMD_WRITE 0x80 /* Write command */
@@ -28,6 +29,8 @@
#define RTC_ADDR_RAM0 0x20 /* Address of RAM0 */
#define RTC_ADDR_TCR 0x08 /* Address of trickle charge register */
+#define RTC_CLCK_BURST 0x1F /* Address of clock burst */
+#define RTC_CLCK_LEN 0x08 /* Size of clock burst */
#define RTC_ADDR_CTRL 0x07 /* Address of control register */
#define RTC_ADDR_YEAR 0x06 /* Address of year register */
#define RTC_ADDR_DAY 0x05 /* Address of day of week register */
@@ -37,217 +40,180 @@
#define RTC_ADDR_MIN 0x01 /* Address of minute register */
#define RTC_ADDR_SEC 0x00 /* Address of second register */
-#ifdef CONFIG_SH_SECUREEDGE5410
-#include <asm/rtc.h>
-#include <mach/secureedge5410.h>
-
-#define RTC_RESET 0x1000
-#define RTC_IODATA 0x0800
-#define RTC_SCLK 0x0400
-
-#define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00)
-#define get_dp() SECUREEDGE_READ_IOPORT()
-#define ds1302_set_tx()
-#define ds1302_set_rx()
-
-static inline int ds1302_hw_init(void)
+static int ds1302_rtc_set_time(struct device *dev, struct rtc_time *time)
{
- return 0;
+ struct spi_device *spi = dev_get_drvdata(dev);
+ u8 buf[1 + RTC_CLCK_LEN];
+ u8 *bp = buf;
+ int status;
+
+ /* Enable writing */
+ bp = buf;
+ *bp++ = RTC_ADDR_CTRL << 1 | RTC_CMD_WRITE;
+ *bp++ = RTC_CMD_WRITE_ENABLE;
+
+ status = spi_write_then_read(spi, buf, 2,
+ NULL, 0);
+ if (!status)
+ return status;
+
+ /* Write registers starting at the first time/date address. */
+ bp = buf;
+ *bp++ = RTC_CLCK_BURST << 1 | RTC_CMD_WRITE;
+
+ *bp++ = bin2bcd(time->tm_sec);
+ *bp++ = bin2bcd(time->tm_min);
+ *bp++ = bin2bcd(time->tm_hour);
+ *bp++ = bin2bcd(time->tm_mday);
+ *bp++ = bin2bcd(time->tm_mon + 1);
+ *bp++ = time->tm_wday;
+ *bp++ = bin2bcd(time->tm_year % 100);
+ *bp++ = RTC_CMD_WRITE_DISABLE;
+
+ /* use write-then-read since dma from stack is nonportable */
+ return spi_write_then_read(spi, buf, sizeof(buf),
+ NULL, 0);
}
-static inline void ds1302_reset(void)
+static int ds1302_rtc_get_time(struct device *dev, struct rtc_time *time)
{
- set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK));
+ struct spi_device *spi = dev_get_drvdata(dev);
+ u8 addr = RTC_CLCK_BURST << 1 | RTC_CMD_READ;
+ u8 buf[RTC_CLCK_LEN - 1];
+ int status;
+
+ /* Use write-then-read to get all the date/time registers
+ * since dma from stack is nonportable
+ */
+ status = spi_write_then_read(spi, &addr, sizeof(addr),
+ buf, sizeof(buf));
+ if (status < 0)
+ return status;
+
+ /* Decode the registers */
+ time->tm_sec = bcd2bin(buf[RTC_ADDR_SEC]);
+ time->tm_min = bcd2bin(buf[RTC_ADDR_MIN]);
+ time->tm_hour = bcd2bin(buf[RTC_ADDR_HOUR]);
+ time->tm_wday = buf[RTC_ADDR_DAY] - 1;
+ time->tm_mday = bcd2bin(buf[RTC_ADDR_DATE]);
+ time->tm_mon = bcd2bin(buf[RTC_ADDR_MON]) - 1;
+ time->tm_year = bcd2bin(buf[RTC_ADDR_YEAR]) + 100;
+
+ /* Time may not be set */
+ return rtc_valid_tm(time);
}
-static inline void ds1302_clock(void)
-{
- set_dp(get_dp() | RTC_SCLK); /* clock high */
- set_dp(get_dp() & ~RTC_SCLK); /* clock low */
-}
-
-static inline void ds1302_start(void)
-{
- set_dp(get_dp() | RTC_RESET);
-}
-
-static inline void ds1302_stop(void)
-{
- set_dp(get_dp() & ~RTC_RESET);
-}
-
-static inline void ds1302_txbit(int bit)
-{
- set_dp((get_dp() & ~RTC_IODATA) | (bit ? RTC_IODATA : 0));
-}
-
-static inline int ds1302_rxbit(void)
-{
- return !!(get_dp() & RTC_IODATA);
-}
-
-#else
-#error "Add support for your platform"
-#endif
+static struct rtc_class_ops ds1302_rtc_ops = {
+ .read_time = ds1302_rtc_get_time,
+ .set_time = ds1302_rtc_set_time,
+};
-static void ds1302_sendbits(unsigned int val)
+static int ds1302_probe(struct spi_device *spi)
{
- int i;
-
- ds1302_set_tx();
-
- for (i = 8; (i); i--, val >>= 1) {
- ds1302_txbit(val & 0x1);
- ds1302_clock();
+ struct rtc_device *rtc;
+ u8 addr;
+ u8 buf[4];
+ u8 *bp = buf;
+ int status;
+
+ /* Sanity check board setup data. This may be hooked up
+ * in 3wire mode, but we don't care. Note that unless
+ * there's an inverter in place, this needs SPI_CS_HIGH!
+ */
+ if (spi->bits_per_word && (spi->bits_per_word != 8)) {
+ dev_err(&spi->dev, "bad word length\n");
+ return -EINVAL;
+ } else if (spi->max_speed_hz > 2000000) {
+ dev_err(&spi->dev, "speed is too high\n");
+ return -EINVAL;
+ } else if (spi->mode & SPI_CPHA) {
+ dev_err(&spi->dev, "bad mode\n");
+ return -EINVAL;
}
-}
-
-static unsigned int ds1302_recvbits(void)
-{
- unsigned int val;
- int i;
-
- ds1302_set_rx();
- for (i = 0, val = 0; (i < 8); i++) {
- val |= (ds1302_rxbit() << i);
- ds1302_clock();
+ addr = RTC_ADDR_CTRL << 1 | RTC_CMD_READ;
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register read error %d\n",
+ status);
+ return status;
}
- return val;
-}
-
-static unsigned int ds1302_readbyte(unsigned int addr)
-{
- unsigned int val;
-
- ds1302_reset();
-
- ds1302_start();
- ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_READ);
- val = ds1302_recvbits();
- ds1302_stop();
-
- return val;
-}
-
-static void ds1302_writebyte(unsigned int addr, unsigned int val)
-{
- ds1302_reset();
-
- ds1302_start();
- ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_WRITE);
- ds1302_sendbits(val);
- ds1302_stop();
-}
-
-static int ds1302_rtc_read_time(struct device *dev, struct rtc_time *tm)
-{
- tm->tm_sec = bcd2bin(ds1302_readbyte(RTC_ADDR_SEC));
- tm->tm_min = bcd2bin(ds1302_readbyte(RTC_ADDR_MIN));
- tm->tm_hour = bcd2bin(ds1302_readbyte(RTC_ADDR_HOUR));
- tm->tm_wday = bcd2bin(ds1302_readbyte(RTC_ADDR_DAY));
- tm->tm_mday = bcd2bin(ds1302_readbyte(RTC_ADDR_DATE));
- tm->tm_mon = bcd2bin(ds1302_readbyte(RTC_ADDR_MON)) - 1;
- tm->tm_year = bcd2bin(ds1302_readbyte(RTC_ADDR_YEAR));
-
- if (tm->tm_year < 70)
- tm->tm_year += 100;
-
- dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
- "mday=%d, mon=%d, year=%d, wday=%d\n",
- __func__,
- tm->tm_sec, tm->tm_min, tm->tm_hour,
- tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
-
- return rtc_valid_tm(tm);
-}
-
-static int ds1302_rtc_set_time(struct device *dev, struct rtc_time *tm)
-{
- ds1302_writebyte(RTC_ADDR_CTRL, RTC_CMD_WRITE_ENABLE);
- /* Stop RTC */
- ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) | 0x80);
-
- ds1302_writebyte(RTC_ADDR_SEC, bin2bcd(tm->tm_sec));
- ds1302_writebyte(RTC_ADDR_MIN, bin2bcd(tm->tm_min));
- ds1302_writebyte(RTC_ADDR_HOUR, bin2bcd(tm->tm_hour));
- ds1302_writebyte(RTC_ADDR_DAY, bin2bcd(tm->tm_wday));
- ds1302_writebyte(RTC_ADDR_DATE, bin2bcd(tm->tm_mday));
- ds1302_writebyte(RTC_ADDR_MON, bin2bcd(tm->tm_mon + 1));
- ds1302_writebyte(RTC_ADDR_YEAR, bin2bcd(tm->tm_year % 100));
+ if ((buf[0] & ~RTC_CMD_WRITE_DISABLE) != 0) {
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register read error %d\n",
+ status);
+ return status;
+ }
+
+ if ((buf[0] & ~RTC_CMD_WRITE_DISABLE) != 0) {
+ dev_err(&spi->dev, "junk in control register\n");
+ return -ENODEV;
+ }
+ }
+ if (buf[0] == 0) {
+ bp = buf;
+ *bp++ = RTC_ADDR_CTRL << 1 | RTC_CMD_WRITE;
+ *bp++ = RTC_CMD_WRITE_DISABLE;
+
+ status = spi_write_then_read(spi, buf, 2, NULL, 0);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register write error %d\n",
+ status);
+ return status;
+ }
+
+ addr = RTC_ADDR_CTRL << 1 | RTC_CMD_READ;
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev,
+ "error %d reading control register\n",
+ status);
+ return status;
+ }
+
+ if (buf[0] != RTC_CMD_WRITE_DISABLE) {
+ dev_err(&spi->dev, "failed to detect chip\n");
+ return -ENODEV;
+ }
+ }
- /* Start RTC */
- ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) & ~0x80);
+ spi_set_drvdata(spi, spi);
- ds1302_writebyte(RTC_ADDR_CTRL, RTC_CMD_WRITE_DISABLE);
+ rtc = devm_rtc_device_register(&spi->dev, "ds1302",
+ &ds1302_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc)) {
+ status = PTR_ERR(rtc);
+ dev_err(&spi->dev, "error %d registering rtc\n", status);
+ return status;
+ }
return 0;
}
-static int ds1302_rtc_ioctl(struct device *dev, unsigned int cmd,
- unsigned long arg)
+static int ds1302_remove(struct spi_device *spi)
{
- switch (cmd) {
-#ifdef RTC_SET_CHARGE
- case RTC_SET_CHARGE:
- {
- int tcs_val;
-
- if (copy_from_user(&tcs_val, (int __user *)arg, sizeof(int)))
- return -EFAULT;
-
- ds1302_writebyte(RTC_ADDR_TCR, (0xa0 | tcs_val * 0xf));
- return 0;
- }
-#endif
- }
-
- return -ENOIOCTLCMD;
+ spi_set_drvdata(spi, NULL);
+ return 0;
}
-static struct rtc_class_ops ds1302_rtc_ops = {
- .read_time = ds1302_rtc_read_time,
- .set_time = ds1302_rtc_set_time,
- .ioctl = ds1302_rtc_ioctl,
+#ifdef CONFIG_OF
+static const struct of_device_id ds1302_dt_ids[] = {
+ { .compatible = "maxim,rtc-ds1302", },
+ { /* sentinel */ }
};
+MODULE_DEVICE_TABLE(of, ds1302_dt_ids);
+#endif
-static int __init ds1302_rtc_probe(struct platform_device *pdev)
-{
- struct rtc_device *rtc;
-
- if (ds1302_hw_init()) {
- dev_err(&pdev->dev, "Failed to init communication channel");
- return -EINVAL;
- }
-
- /* Reset */
- ds1302_reset();
-
- /* Write a magic value to the DS1302 RAM, and see if it sticks. */
- ds1302_writebyte(RTC_ADDR_RAM0, 0x42);
- if (ds1302_readbyte(RTC_ADDR_RAM0) != 0x42) {
- dev_err(&pdev->dev, "Failed to probe");
- return -ENODEV;
- }
-
- rtc = devm_rtc_device_register(&pdev->dev, "ds1302",
- &ds1302_rtc_ops, THIS_MODULE);
- if (IS_ERR(rtc))
- return PTR_ERR(rtc);
-
- platform_set_drvdata(pdev, rtc);
-
- return 0;
-}
-
-static struct platform_driver ds1302_platform_driver = {
- .driver = {
- .name = DRV_NAME,
- },
+static struct spi_driver ds1302_driver = {
+ .driver.name = "rtc-ds1302",
+ .driver.of_match_table = of_match_ptr(ds1302_dt_ids),
+ .probe = ds1302_probe,
+ .remove = ds1302_remove,
};
-module_platform_driver_probe(ds1302_platform_driver, ds1302_rtc_probe);
+module_spi_driver(ds1302_driver);
MODULE_DESCRIPTION("Dallas DS1302 RTC driver");
MODULE_VERSION(DRV_VERSION);
--
2.6.3
--
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^ permalink raw reply related [flat|nested] 38+ messages in thread* Re: [PATCH v6] rtc: rewrite DS1302 using SPI
2016-02-22 1:41 ` [rtc-linux] " Sergei Ianovich
(?)
@ 2016-02-22 18:45 ` Rob Herring
-1 siblings, 0 replies; 38+ messages in thread
From: Rob Herring @ 2016-02-22 18:45 UTC (permalink / raw)
To: Sergei Ianovich
Cc: linux-kernel, Alexandre Belloni, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK SUBSYSTEM
On Mon, Feb 22, 2016 at 04:41:22AM +0300, Sergei Ianovich wrote:
> DS1302 is half-duplex SPI device. The driver respects this fact now.
>
> Pin configurations should be implemented using SPI subsystem.
>
> Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
> CC: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> CC: Rob Herring <robh@kernel.org>
> ---
> v5..v6
> * rewrite the driver as an SPI slave device
> * use "maxim" for vendor name per Kconfig
> * stop touching device RAM in device presence test
> * only return time from device if valid
> * use burst mode for reading/writing time
> * droppped charging control. I cannot test it, and it looks broken
>
> v4..v5
> * drop THIS_MODULE from struct platform driver
> * use "dallas" for vendor name per vendor-prefixes.txt
>
> v3..v4
> * move DTS bindings to a different patch
>
> v2..v3
> * use usleep_range instead of custom nsleep
> * number change (07/16 -> 09/21)
>
> v0..v2
> * use device tree
> * use devm helpers where possible
>
> .../devicetree/bindings/rtc/rtc-ds1302.txt | 46 +++
> drivers/rtc/Kconfig | 15 +-
> drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
> 3 files changed, 212 insertions(+), 197 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
>
> diff --git a/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt b/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
> new file mode 100644
> index 0000000..b6c0973
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
> @@ -0,0 +1,46 @@
> +* Maxim/Dallas Semiconductor DS-1302 RTC
> +
> +Simple device which could be used to store date/time between reboots.
> +
> +The device uses the standard MicroWire half-duplex transfer timing.
> +Master output is set on low clock and sensed by the RTC on the rising
> +edge. Master input is set by the RTC on the trailing edge and is sensed
> +by the master on low clock.
> +
> +Required properties:
> +
> +- compatible : Should be "maxim,rtc-ds1302"
Just maxim,ds1032. RTC is implied by the part number and inline with
existing dallas,ds1307.
> +
> +Required SPI properties:
> +
> +- reg : Should be address of the device chip select within
> + the controller.
> +
> +- spi-max-frequency : DS-1302 has 500 kHz if powered at 2.2V,
> + and 2MHz if powered at 5V.
> +
> +- spi-3wire : The device has a shared signal IN/OUT line.
> +
> +- spi-lsb-first : DS-1302 requires least significant bit first
> + transfers.
> +
> +- spi-cs-high: DS-1302 has active high chip select line. This is
> + required unless inverted in hardware.
> +
> +Example:
> +
> +spi0@901c {
spi@...
> + #address-cells = <1>;
> + #size-cells = <0>;
> + compatible = "icpdas,spi-lp8841-rtc";
And this will need updating...
> + reg = <0x901c 0x1>;
> +
> + rtc@0 {
> + compatible = "maxim,rtc-ds1302";
> + reg = <0>;
> + spi-max-frequency = <500000>;
> + spi-3wire;
> + spi-lsb-first;
> + spi-cs-high;
> + };
> +};
^ permalink raw reply [flat|nested] 38+ messages in thread* Re: [PATCH v6] rtc: rewrite DS1302 using SPI
@ 2016-02-22 18:45 ` Rob Herring
0 siblings, 0 replies; 38+ messages in thread
From: Rob Herring @ 2016-02-22 18:45 UTC (permalink / raw)
To: Sergei Ianovich
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA, Alexandre Belloni,
Pawel Moll, Mark Rutland, Ian Campbell, Kumar Gala,
Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK SUBSYSTEM
On Mon, Feb 22, 2016 at 04:41:22AM +0300, Sergei Ianovich wrote:
> DS1302 is half-duplex SPI device. The driver respects this fact now.
>
> Pin configurations should be implemented using SPI subsystem.
>
> Signed-off-by: Sergei Ianovich <ynvich-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> CC: Alexandre Belloni <alexandre.belloni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> CC: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> ---
> v5..v6
> * rewrite the driver as an SPI slave device
> * use "maxim" for vendor name per Kconfig
> * stop touching device RAM in device presence test
> * only return time from device if valid
> * use burst mode for reading/writing time
> * droppped charging control. I cannot test it, and it looks broken
>
> v4..v5
> * drop THIS_MODULE from struct platform driver
> * use "dallas" for vendor name per vendor-prefixes.txt
>
> v3..v4
> * move DTS bindings to a different patch
>
> v2..v3
> * use usleep_range instead of custom nsleep
> * number change (07/16 -> 09/21)
>
> v0..v2
> * use device tree
> * use devm helpers where possible
>
> .../devicetree/bindings/rtc/rtc-ds1302.txt | 46 +++
> drivers/rtc/Kconfig | 15 +-
> drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
> 3 files changed, 212 insertions(+), 197 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
>
> diff --git a/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt b/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
> new file mode 100644
> index 0000000..b6c0973
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
> @@ -0,0 +1,46 @@
> +* Maxim/Dallas Semiconductor DS-1302 RTC
> +
> +Simple device which could be used to store date/time between reboots.
> +
> +The device uses the standard MicroWire half-duplex transfer timing.
> +Master output is set on low clock and sensed by the RTC on the rising
> +edge. Master input is set by the RTC on the trailing edge and is sensed
> +by the master on low clock.
> +
> +Required properties:
> +
> +- compatible : Should be "maxim,rtc-ds1302"
Just maxim,ds1032. RTC is implied by the part number and inline with
existing dallas,ds1307.
> +
> +Required SPI properties:
> +
> +- reg : Should be address of the device chip select within
> + the controller.
> +
> +- spi-max-frequency : DS-1302 has 500 kHz if powered at 2.2V,
> + and 2MHz if powered at 5V.
> +
> +- spi-3wire : The device has a shared signal IN/OUT line.
> +
> +- spi-lsb-first : DS-1302 requires least significant bit first
> + transfers.
> +
> +- spi-cs-high: DS-1302 has active high chip select line. This is
> + required unless inverted in hardware.
> +
> +Example:
> +
> +spi0@901c {
spi@...
> + #address-cells = <1>;
> + #size-cells = <0>;
> + compatible = "icpdas,spi-lp8841-rtc";
And this will need updating...
> + reg = <0x901c 0x1>;
> +
> + rtc@0 {
> + compatible = "maxim,rtc-ds1302";
> + reg = <0>;
> + spi-max-frequency = <500000>;
> + spi-3wire;
> + spi-lsb-first;
> + spi-cs-high;
> + };
> +};
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
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More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 38+ messages in thread* [rtc-linux] Re: [PATCH v6] rtc: rewrite DS1302 using SPI
@ 2016-02-22 18:45 ` Rob Herring
0 siblings, 0 replies; 38+ messages in thread
From: Rob Herring @ 2016-02-22 18:45 UTC (permalink / raw)
To: Sergei Ianovich
Cc: linux-kernel, Alexandre Belloni, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK SUBSYSTEM
On Mon, Feb 22, 2016 at 04:41:22AM +0300, Sergei Ianovich wrote:
> DS1302 is half-duplex SPI device. The driver respects this fact now.
>
> Pin configurations should be implemented using SPI subsystem.
>
> Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
> CC: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> CC: Rob Herring <robh@kernel.org>
> ---
> v5..v6
> * rewrite the driver as an SPI slave device
> * use "maxim" for vendor name per Kconfig
> * stop touching device RAM in device presence test
> * only return time from device if valid
> * use burst mode for reading/writing time
> * droppped charging control. I cannot test it, and it looks broken
>
> v4..v5
> * drop THIS_MODULE from struct platform driver
> * use "dallas" for vendor name per vendor-prefixes.txt
>
> v3..v4
> * move DTS bindings to a different patch
>
> v2..v3
> * use usleep_range instead of custom nsleep
> * number change (07/16 -> 09/21)
>
> v0..v2
> * use device tree
> * use devm helpers where possible
>
> .../devicetree/bindings/rtc/rtc-ds1302.txt | 46 +++
> drivers/rtc/Kconfig | 15 +-
> drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
> 3 files changed, 212 insertions(+), 197 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
>
> diff --git a/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt b/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
> new file mode 100644
> index 0000000..b6c0973
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/rtc/rtc-ds1302.txt
> @@ -0,0 +1,46 @@
> +* Maxim/Dallas Semiconductor DS-1302 RTC
> +
> +Simple device which could be used to store date/time between reboots.
> +
> +The device uses the standard MicroWire half-duplex transfer timing.
> +Master output is set on low clock and sensed by the RTC on the rising
> +edge. Master input is set by the RTC on the trailing edge and is sensed
> +by the master on low clock.
> +
> +Required properties:
> +
> +- compatible : Should be "maxim,rtc-ds1302"
Just maxim,ds1032. RTC is implied by the part number and inline with
existing dallas,ds1307.
> +
> +Required SPI properties:
> +
> +- reg : Should be address of the device chip select within
> + the controller.
> +
> +- spi-max-frequency : DS-1302 has 500 kHz if powered at 2.2V,
> + and 2MHz if powered at 5V.
> +
> +- spi-3wire : The device has a shared signal IN/OUT line.
> +
> +- spi-lsb-first : DS-1302 requires least significant bit first
> + transfers.
> +
> +- spi-cs-high: DS-1302 has active high chip select line. This is
> + required unless inverted in hardware.
> +
> +Example:
> +
> +spi0@901c {
spi@...
> + #address-cells = <1>;
> + #size-cells = <0>;
> + compatible = "icpdas,spi-lp8841-rtc";
And this will need updating...
> + reg = <0x901c 0x1>;
> +
> + rtc@0 {
> + compatible = "maxim,rtc-ds1302";
> + reg = <0>;
> + spi-max-frequency = <500000>;
> + spi-3wire;
> + spi-lsb-first;
> + spi-cs-high;
> + };
> +};
--
--
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Membership options at http://groups.google.com/group/rtc-linux .
Please read http://groups.google.com/group/rtc-linux/web/checklist
before submitting a driver.
---
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^ permalink raw reply [flat|nested] 38+ messages in thread
* [PATCH v7] rtc: rewrite DS1302 using SPI
2016-02-22 1:41 ` [rtc-linux] " Sergei Ianovich
@ 2016-02-23 10:54 ` Sergei Ianovich
-1 siblings, 0 replies; 38+ messages in thread
From: Sergei Ianovich @ 2016-02-23 10:54 UTC (permalink / raw)
To: linux-kernel
Cc: Sergei Ianovich, Alexandre Belloni, Rob Herring, Rob Herring,
Pawel Moll, Mark Rutland, Ian Campbell, Kumar Gala,
Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM
DS1302 is half-duplex SPI device. The driver respects this fact now.
Pin configurations should be implemented using SPI subsystem.
Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
CC: Alexandre Belloni <alexandre.belloni@free-electrons.com>
CC: Rob Herring <robh@kernel.org>
v6..v7
* change binding and doc file names
v5..v6
* rewrite the driver as an SPI slave device
* use "maxim" for vendor name per Kconfig
* stop changing device RAM in device presence test
* only return time from device if valid
* use burst mode for reading/writing time
* dropped charging control. I cannot test it, and it looks broken
v4..v5
* drop THIS_MODULE from struct platform driver
* use "dallas" for vendor name per vendor-prefixes.txt
v3..v4
* move DTS bindings to a different patch
v2..v3
* use usleep_range instead of custom nsleep
* number change (07/16 -> 09/21)
v0..v2
* use device tree
* use devm helpers where possible
---
.../devicetree/bindings/rtc/maxim-ds1302.txt | 46 +++
drivers/rtc/Kconfig | 15 +-
drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
3 files changed, 212 insertions(+), 197 deletions(-)
create mode 100644 Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
diff --git a/Documentation/devicetree/bindings/rtc/maxim-ds1302.txt b/Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
new file mode 100644
index 0000000..ba470c5
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
@@ -0,0 +1,46 @@
+* Maxim/Dallas Semiconductor DS-1302 RTC
+
+Simple device which could be used to store date/time between reboots.
+
+The device uses the standard MicroWire half-duplex transfer timing.
+Master output is set on low clock and sensed by the RTC on the rising
+edge. Master input is set by the RTC on the trailing edge and is sensed
+by the master on low clock.
+
+Required properties:
+
+- compatible : Should be "maxim,ds1302"
+
+Required SPI properties:
+
+- reg : Should be address of the device chip select within
+ the controller.
+
+- spi-max-frequency : DS-1302 has 500 kHz if powered at 2.2V,
+ and 2MHz if powered at 5V.
+
+- spi-3wire : The device has a shared signal IN/OUT line.
+
+- spi-lsb-first : DS-1302 requires least significant bit first
+ transfers.
+
+- spi-cs-high: DS-1302 has active high chip select line. This is
+ required unless inverted in hardware.
+
+Example:
+
+spi@901c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "icpdas,lp8841-spi-rtc";
+ reg = <0x901c 0x1>;
+
+ rtc@0 {
+ compatible = "maxim,ds1302";
+ reg = <0>;
+ spi-max-frequency = <500000>;
+ spi-3wire;
+ spi-lsb-first;
+ spi-cs-high;
+ };
+};
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 376322f..e20e804 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -646,6 +646,15 @@ config RTC_DRV_M41T94
This driver can also be built as a module. If so, the module
will be called rtc-m41t94.
+config RTC_DRV_DS1302
+ tristate "Dallas/Maxim DS1302"
+ depends on SPI
+ help
+ If you say yes here you get support for the Dallas DS1302 RTC chips.
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-ds1302.
+
config RTC_DRV_DS1305
tristate "Dallas/Maxim DS1305/DS1306"
help
@@ -811,12 +820,6 @@ config RTC_DRV_DS1286
help
If you say yes here you get support for the Dallas DS1286 RTC chips.
-config RTC_DRV_DS1302
- tristate "Dallas DS1302"
- depends on SH_SECUREEDGE5410
- help
- If you say yes here you get support for the Dallas DS1302 RTC chips.
-
config RTC_DRV_DS1511
tristate "Dallas DS1511"
depends on HAS_IOMEM
diff --git a/drivers/rtc/rtc-ds1302.c b/drivers/rtc/rtc-ds1302.c
index 6bef7a5..5cdc0f2 100644
--- a/drivers/rtc/rtc-ds1302.c
+++ b/drivers/rtc/rtc-ds1302.c
@@ -9,16 +9,17 @@
* this archive for more details.
*/
+#include <linux/bcd.h>
#include <linux/init.h>
-#include <linux/module.h>
+#include <linux/io.h>
#include <linux/kernel.h>
-#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/of.h>
#include <linux/rtc.h>
-#include <linux/io.h>
-#include <linux/bcd.h>
+#include <linux/spi/spi.h>
#define DRV_NAME "rtc-ds1302"
-#define DRV_VERSION "0.1.1"
+#define DRV_VERSION "1.0.0"
#define RTC_CMD_READ 0x81 /* Read command */
#define RTC_CMD_WRITE 0x80 /* Write command */
@@ -28,6 +29,8 @@
#define RTC_ADDR_RAM0 0x20 /* Address of RAM0 */
#define RTC_ADDR_TCR 0x08 /* Address of trickle charge register */
+#define RTC_CLCK_BURST 0x1F /* Address of clock burst */
+#define RTC_CLCK_LEN 0x08 /* Size of clock burst */
#define RTC_ADDR_CTRL 0x07 /* Address of control register */
#define RTC_ADDR_YEAR 0x06 /* Address of year register */
#define RTC_ADDR_DAY 0x05 /* Address of day of week register */
@@ -37,217 +40,180 @@
#define RTC_ADDR_MIN 0x01 /* Address of minute register */
#define RTC_ADDR_SEC 0x00 /* Address of second register */
-#ifdef CONFIG_SH_SECUREEDGE5410
-#include <asm/rtc.h>
-#include <mach/secureedge5410.h>
-
-#define RTC_RESET 0x1000
-#define RTC_IODATA 0x0800
-#define RTC_SCLK 0x0400
-
-#define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00)
-#define get_dp() SECUREEDGE_READ_IOPORT()
-#define ds1302_set_tx()
-#define ds1302_set_rx()
-
-static inline int ds1302_hw_init(void)
+static int ds1302_rtc_set_time(struct device *dev, struct rtc_time *time)
{
- return 0;
+ struct spi_device *spi = dev_get_drvdata(dev);
+ u8 buf[1 + RTC_CLCK_LEN];
+ u8 *bp = buf;
+ int status;
+
+ /* Enable writing */
+ bp = buf;
+ *bp++ = RTC_ADDR_CTRL << 1 | RTC_CMD_WRITE;
+ *bp++ = RTC_CMD_WRITE_ENABLE;
+
+ status = spi_write_then_read(spi, buf, 2,
+ NULL, 0);
+ if (!status)
+ return status;
+
+ /* Write registers starting at the first time/date address. */
+ bp = buf;
+ *bp++ = RTC_CLCK_BURST << 1 | RTC_CMD_WRITE;
+
+ *bp++ = bin2bcd(time->tm_sec);
+ *bp++ = bin2bcd(time->tm_min);
+ *bp++ = bin2bcd(time->tm_hour);
+ *bp++ = bin2bcd(time->tm_mday);
+ *bp++ = bin2bcd(time->tm_mon + 1);
+ *bp++ = time->tm_wday;
+ *bp++ = bin2bcd(time->tm_year % 100);
+ *bp++ = RTC_CMD_WRITE_DISABLE;
+
+ /* use write-then-read since dma from stack is nonportable */
+ return spi_write_then_read(spi, buf, sizeof(buf),
+ NULL, 0);
}
-static inline void ds1302_reset(void)
+static int ds1302_rtc_get_time(struct device *dev, struct rtc_time *time)
{
- set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK));
+ struct spi_device *spi = dev_get_drvdata(dev);
+ u8 addr = RTC_CLCK_BURST << 1 | RTC_CMD_READ;
+ u8 buf[RTC_CLCK_LEN - 1];
+ int status;
+
+ /* Use write-then-read to get all the date/time registers
+ * since dma from stack is nonportable
+ */
+ status = spi_write_then_read(spi, &addr, sizeof(addr),
+ buf, sizeof(buf));
+ if (status < 0)
+ return status;
+
+ /* Decode the registers */
+ time->tm_sec = bcd2bin(buf[RTC_ADDR_SEC]);
+ time->tm_min = bcd2bin(buf[RTC_ADDR_MIN]);
+ time->tm_hour = bcd2bin(buf[RTC_ADDR_HOUR]);
+ time->tm_wday = buf[RTC_ADDR_DAY] - 1;
+ time->tm_mday = bcd2bin(buf[RTC_ADDR_DATE]);
+ time->tm_mon = bcd2bin(buf[RTC_ADDR_MON]) - 1;
+ time->tm_year = bcd2bin(buf[RTC_ADDR_YEAR]) + 100;
+
+ /* Time may not be set */
+ return rtc_valid_tm(time);
}
-static inline void ds1302_clock(void)
-{
- set_dp(get_dp() | RTC_SCLK); /* clock high */
- set_dp(get_dp() & ~RTC_SCLK); /* clock low */
-}
-
-static inline void ds1302_start(void)
-{
- set_dp(get_dp() | RTC_RESET);
-}
-
-static inline void ds1302_stop(void)
-{
- set_dp(get_dp() & ~RTC_RESET);
-}
-
-static inline void ds1302_txbit(int bit)
-{
- set_dp((get_dp() & ~RTC_IODATA) | (bit ? RTC_IODATA : 0));
-}
-
-static inline int ds1302_rxbit(void)
-{
- return !!(get_dp() & RTC_IODATA);
-}
-
-#else
-#error "Add support for your platform"
-#endif
+static struct rtc_class_ops ds1302_rtc_ops = {
+ .read_time = ds1302_rtc_get_time,
+ .set_time = ds1302_rtc_set_time,
+};
-static void ds1302_sendbits(unsigned int val)
+static int ds1302_probe(struct spi_device *spi)
{
- int i;
-
- ds1302_set_tx();
-
- for (i = 8; (i); i--, val >>= 1) {
- ds1302_txbit(val & 0x1);
- ds1302_clock();
+ struct rtc_device *rtc;
+ u8 addr;
+ u8 buf[4];
+ u8 *bp = buf;
+ int status;
+
+ /* Sanity check board setup data. This may be hooked up
+ * in 3wire mode, but we don't care. Note that unless
+ * there's an inverter in place, this needs SPI_CS_HIGH!
+ */
+ if (spi->bits_per_word && (spi->bits_per_word != 8)) {
+ dev_err(&spi->dev, "bad word length\n");
+ return -EINVAL;
+ } else if (spi->max_speed_hz > 2000000) {
+ dev_err(&spi->dev, "speed is too high\n");
+ return -EINVAL;
+ } else if (spi->mode & SPI_CPHA) {
+ dev_err(&spi->dev, "bad mode\n");
+ return -EINVAL;
}
-}
-
-static unsigned int ds1302_recvbits(void)
-{
- unsigned int val;
- int i;
-
- ds1302_set_rx();
- for (i = 0, val = 0; (i < 8); i++) {
- val |= (ds1302_rxbit() << i);
- ds1302_clock();
+ addr = RTC_ADDR_CTRL << 1 | RTC_CMD_READ;
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register read error %d\n",
+ status);
+ return status;
}
- return val;
-}
-
-static unsigned int ds1302_readbyte(unsigned int addr)
-{
- unsigned int val;
-
- ds1302_reset();
-
- ds1302_start();
- ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_READ);
- val = ds1302_recvbits();
- ds1302_stop();
-
- return val;
-}
-
-static void ds1302_writebyte(unsigned int addr, unsigned int val)
-{
- ds1302_reset();
-
- ds1302_start();
- ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_WRITE);
- ds1302_sendbits(val);
- ds1302_stop();
-}
-
-static int ds1302_rtc_read_time(struct device *dev, struct rtc_time *tm)
-{
- tm->tm_sec = bcd2bin(ds1302_readbyte(RTC_ADDR_SEC));
- tm->tm_min = bcd2bin(ds1302_readbyte(RTC_ADDR_MIN));
- tm->tm_hour = bcd2bin(ds1302_readbyte(RTC_ADDR_HOUR));
- tm->tm_wday = bcd2bin(ds1302_readbyte(RTC_ADDR_DAY));
- tm->tm_mday = bcd2bin(ds1302_readbyte(RTC_ADDR_DATE));
- tm->tm_mon = bcd2bin(ds1302_readbyte(RTC_ADDR_MON)) - 1;
- tm->tm_year = bcd2bin(ds1302_readbyte(RTC_ADDR_YEAR));
-
- if (tm->tm_year < 70)
- tm->tm_year += 100;
-
- dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
- "mday=%d, mon=%d, year=%d, wday=%d\n",
- __func__,
- tm->tm_sec, tm->tm_min, tm->tm_hour,
- tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
-
- return rtc_valid_tm(tm);
-}
-
-static int ds1302_rtc_set_time(struct device *dev, struct rtc_time *tm)
-{
- ds1302_writebyte(RTC_ADDR_CTRL, RTC_CMD_WRITE_ENABLE);
- /* Stop RTC */
- ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) | 0x80);
-
- ds1302_writebyte(RTC_ADDR_SEC, bin2bcd(tm->tm_sec));
- ds1302_writebyte(RTC_ADDR_MIN, bin2bcd(tm->tm_min));
- ds1302_writebyte(RTC_ADDR_HOUR, bin2bcd(tm->tm_hour));
- ds1302_writebyte(RTC_ADDR_DAY, bin2bcd(tm->tm_wday));
- ds1302_writebyte(RTC_ADDR_DATE, bin2bcd(tm->tm_mday));
- ds1302_writebyte(RTC_ADDR_MON, bin2bcd(tm->tm_mon + 1));
- ds1302_writebyte(RTC_ADDR_YEAR, bin2bcd(tm->tm_year % 100));
+ if ((buf[0] & ~RTC_CMD_WRITE_DISABLE) != 0) {
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register read error %d\n",
+ status);
+ return status;
+ }
+
+ if ((buf[0] & ~RTC_CMD_WRITE_DISABLE) != 0) {
+ dev_err(&spi->dev, "junk in control register\n");
+ return -ENODEV;
+ }
+ }
+ if (buf[0] == 0) {
+ bp = buf;
+ *bp++ = RTC_ADDR_CTRL << 1 | RTC_CMD_WRITE;
+ *bp++ = RTC_CMD_WRITE_DISABLE;
+
+ status = spi_write_then_read(spi, buf, 2, NULL, 0);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register write error %d\n",
+ status);
+ return status;
+ }
+
+ addr = RTC_ADDR_CTRL << 1 | RTC_CMD_READ;
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev,
+ "error %d reading control register\n",
+ status);
+ return status;
+ }
+
+ if (buf[0] != RTC_CMD_WRITE_DISABLE) {
+ dev_err(&spi->dev, "failed to detect chip\n");
+ return -ENODEV;
+ }
+ }
- /* Start RTC */
- ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) & ~0x80);
+ spi_set_drvdata(spi, spi);
- ds1302_writebyte(RTC_ADDR_CTRL, RTC_CMD_WRITE_DISABLE);
+ rtc = devm_rtc_device_register(&spi->dev, "ds1302",
+ &ds1302_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc)) {
+ status = PTR_ERR(rtc);
+ dev_err(&spi->dev, "error %d registering rtc\n", status);
+ return status;
+ }
return 0;
}
-static int ds1302_rtc_ioctl(struct device *dev, unsigned int cmd,
- unsigned long arg)
+static int ds1302_remove(struct spi_device *spi)
{
- switch (cmd) {
-#ifdef RTC_SET_CHARGE
- case RTC_SET_CHARGE:
- {
- int tcs_val;
-
- if (copy_from_user(&tcs_val, (int __user *)arg, sizeof(int)))
- return -EFAULT;
-
- ds1302_writebyte(RTC_ADDR_TCR, (0xa0 | tcs_val * 0xf));
- return 0;
- }
-#endif
- }
-
- return -ENOIOCTLCMD;
+ spi_set_drvdata(spi, NULL);
+ return 0;
}
-static struct rtc_class_ops ds1302_rtc_ops = {
- .read_time = ds1302_rtc_read_time,
- .set_time = ds1302_rtc_set_time,
- .ioctl = ds1302_rtc_ioctl,
+#ifdef CONFIG_OF
+static const struct of_device_id ds1302_dt_ids[] = {
+ { .compatible = "maxim,ds1302", },
+ { /* sentinel */ }
};
+MODULE_DEVICE_TABLE(of, ds1302_dt_ids);
+#endif
-static int __init ds1302_rtc_probe(struct platform_device *pdev)
-{
- struct rtc_device *rtc;
-
- if (ds1302_hw_init()) {
- dev_err(&pdev->dev, "Failed to init communication channel");
- return -EINVAL;
- }
-
- /* Reset */
- ds1302_reset();
-
- /* Write a magic value to the DS1302 RAM, and see if it sticks. */
- ds1302_writebyte(RTC_ADDR_RAM0, 0x42);
- if (ds1302_readbyte(RTC_ADDR_RAM0) != 0x42) {
- dev_err(&pdev->dev, "Failed to probe");
- return -ENODEV;
- }
-
- rtc = devm_rtc_device_register(&pdev->dev, "ds1302",
- &ds1302_rtc_ops, THIS_MODULE);
- if (IS_ERR(rtc))
- return PTR_ERR(rtc);
-
- platform_set_drvdata(pdev, rtc);
-
- return 0;
-}
-
-static struct platform_driver ds1302_platform_driver = {
- .driver = {
- .name = DRV_NAME,
- },
+static struct spi_driver ds1302_driver = {
+ .driver.name = "rtc-ds1302",
+ .driver.of_match_table = of_match_ptr(ds1302_dt_ids),
+ .probe = ds1302_probe,
+ .remove = ds1302_remove,
};
-module_platform_driver_probe(ds1302_platform_driver, ds1302_rtc_probe);
+module_spi_driver(ds1302_driver);
MODULE_DESCRIPTION("Dallas DS1302 RTC driver");
MODULE_VERSION(DRV_VERSION);
--
2.7.0
^ permalink raw reply related [flat|nested] 38+ messages in thread* [PATCH v7] rtc: rewrite DS1302 using SPI
@ 2016-02-23 10:54 ` Sergei Ianovich
0 siblings, 0 replies; 38+ messages in thread
From: Sergei Ianovich @ 2016-02-23 10:54 UTC (permalink / raw)
To: linux-kernel
Cc: Sergei Ianovich, Alexandre Belloni, Rob Herring, Rob Herring,
Pawel Moll, Mark Rutland, Ian Campbell, Kumar Gala,
Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM
DS1302 is half-duplex SPI device. The driver respects this fact now.
Pin configurations should be implemented using SPI subsystem.
Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
CC: Alexandre Belloni <alexandre.belloni@free-electrons.com>
CC: Rob Herring <robh@kernel.org>
v6..v7
* change binding and doc file names
v5..v6
* rewrite the driver as an SPI slave device
* use "maxim" for vendor name per Kconfig
* stop changing device RAM in device presence test
* only return time from device if valid
* use burst mode for reading/writing time
* dropped charging control. I cannot test it, and it looks broken
v4..v5
* drop THIS_MODULE from struct platform driver
* use "dallas" for vendor name per vendor-prefixes.txt
v3..v4
* move DTS bindings to a different patch
v2..v3
* use usleep_range instead of custom nsleep
* number change (07/16 -> 09/21)
v0..v2
* use device tree
* use devm helpers where possible
---
.../devicetree/bindings/rtc/maxim-ds1302.txt | 46 +++
drivers/rtc/Kconfig | 15 +-
drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
3 files changed, 212 insertions(+), 197 deletions(-)
create mode 100644 Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
diff --git a/Documentation/devicetree/bindings/rtc/maxim-ds1302.txt b/Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
new file mode 100644
index 0000000..ba470c5
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
@@ -0,0 +1,46 @@
+* Maxim/Dallas Semiconductor DS-1302 RTC
+
+Simple device which could be used to store date/time between reboots.
+
+The device uses the standard MicroWire half-duplex transfer timing.
+Master output is set on low clock and sensed by the RTC on the rising
+edge. Master input is set by the RTC on the trailing edge and is sensed
+by the master on low clock.
+
+Required properties:
+
+- compatible : Should be "maxim,ds1302"
+
+Required SPI properties:
+
+- reg : Should be address of the device chip select within
+ the controller.
+
+- spi-max-frequency : DS-1302 has 500 kHz if powered at 2.2V,
+ and 2MHz if powered at 5V.
+
+- spi-3wire : The device has a shared signal IN/OUT line.
+
+- spi-lsb-first : DS-1302 requires least significant bit first
+ transfers.
+
+- spi-cs-high: DS-1302 has active high chip select line. This is
+ required unless inverted in hardware.
+
+Example:
+
+spi@901c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "icpdas,lp8841-spi-rtc";
+ reg = <0x901c 0x1>;
+
+ rtc@0 {
+ compatible = "maxim,ds1302";
+ reg = <0>;
+ spi-max-frequency = <500000>;
+ spi-3wire;
+ spi-lsb-first;
+ spi-cs-high;
+ };
+};
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 376322f..e20e804 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -646,6 +646,15 @@ config RTC_DRV_M41T94
This driver can also be built as a module. If so, the module
will be called rtc-m41t94.
+config RTC_DRV_DS1302
+ tristate "Dallas/Maxim DS1302"
+ depends on SPI
+ help
+ If you say yes here you get support for the Dallas DS1302 RTC chips.
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-ds1302.
+
config RTC_DRV_DS1305
tristate "Dallas/Maxim DS1305/DS1306"
help
@@ -811,12 +820,6 @@ config RTC_DRV_DS1286
help
If you say yes here you get support for the Dallas DS1286 RTC chips.
-config RTC_DRV_DS1302
- tristate "Dallas DS1302"
- depends on SH_SECUREEDGE5410
- help
- If you say yes here you get support for the Dallas DS1302 RTC chips.
-
config RTC_DRV_DS1511
tristate "Dallas DS1511"
depends on HAS_IOMEM
diff --git a/drivers/rtc/rtc-ds1302.c b/drivers/rtc/rtc-ds1302.c
index 6bef7a5..5cdc0f2 100644
--- a/drivers/rtc/rtc-ds1302.c
+++ b/drivers/rtc/rtc-ds1302.c
@@ -9,16 +9,17 @@
* this archive for more details.
*/
+#include <linux/bcd.h>
#include <linux/init.h>
-#include <linux/module.h>
+#include <linux/io.h>
#include <linux/kernel.h>
-#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/of.h>
#include <linux/rtc.h>
-#include <linux/io.h>
-#include <linux/bcd.h>
+#include <linux/spi/spi.h>
#define DRV_NAME "rtc-ds1302"
-#define DRV_VERSION "0.1.1"
+#define DRV_VERSION "1.0.0"
#define RTC_CMD_READ 0x81 /* Read command */
#define RTC_CMD_WRITE 0x80 /* Write command */
@@ -28,6 +29,8 @@
#define RTC_ADDR_RAM0 0x20 /* Address of RAM0 */
#define RTC_ADDR_TCR 0x08 /* Address of trickle charge register */
+#define RTC_CLCK_BURST 0x1F /* Address of clock burst */
+#define RTC_CLCK_LEN 0x08 /* Size of clock burst */
#define RTC_ADDR_CTRL 0x07 /* Address of control register */
#define RTC_ADDR_YEAR 0x06 /* Address of year register */
#define RTC_ADDR_DAY 0x05 /* Address of day of week register */
@@ -37,217 +40,180 @@
#define RTC_ADDR_MIN 0x01 /* Address of minute register */
#define RTC_ADDR_SEC 0x00 /* Address of second register */
-#ifdef CONFIG_SH_SECUREEDGE5410
-#include <asm/rtc.h>
-#include <mach/secureedge5410.h>
-
-#define RTC_RESET 0x1000
-#define RTC_IODATA 0x0800
-#define RTC_SCLK 0x0400
-
-#define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00)
-#define get_dp() SECUREEDGE_READ_IOPORT()
-#define ds1302_set_tx()
-#define ds1302_set_rx()
-
-static inline int ds1302_hw_init(void)
+static int ds1302_rtc_set_time(struct device *dev, struct rtc_time *time)
{
- return 0;
+ struct spi_device *spi = dev_get_drvdata(dev);
+ u8 buf[1 + RTC_CLCK_LEN];
+ u8 *bp = buf;
+ int status;
+
+ /* Enable writing */
+ bp = buf;
+ *bp++ = RTC_ADDR_CTRL << 1 | RTC_CMD_WRITE;
+ *bp++ = RTC_CMD_WRITE_ENABLE;
+
+ status = spi_write_then_read(spi, buf, 2,
+ NULL, 0);
+ if (!status)
+ return status;
+
+ /* Write registers starting at the first time/date address. */
+ bp = buf;
+ *bp++ = RTC_CLCK_BURST << 1 | RTC_CMD_WRITE;
+
+ *bp++ = bin2bcd(time->tm_sec);
+ *bp++ = bin2bcd(time->tm_min);
+ *bp++ = bin2bcd(time->tm_hour);
+ *bp++ = bin2bcd(time->tm_mday);
+ *bp++ = bin2bcd(time->tm_mon + 1);
+ *bp++ = time->tm_wday;
+ *bp++ = bin2bcd(time->tm_year % 100);
+ *bp++ = RTC_CMD_WRITE_DISABLE;
+
+ /* use write-then-read since dma from stack is nonportable */
+ return spi_write_then_read(spi, buf, sizeof(buf),
+ NULL, 0);
}
-static inline void ds1302_reset(void)
+static int ds1302_rtc_get_time(struct device *dev, struct rtc_time *time)
{
- set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK));
+ struct spi_device *spi = dev_get_drvdata(dev);
+ u8 addr = RTC_CLCK_BURST << 1 | RTC_CMD_READ;
+ u8 buf[RTC_CLCK_LEN - 1];
+ int status;
+
+ /* Use write-then-read to get all the date/time registers
+ * since dma from stack is nonportable
+ */
+ status = spi_write_then_read(spi, &addr, sizeof(addr),
+ buf, sizeof(buf));
+ if (status < 0)
+ return status;
+
+ /* Decode the registers */
+ time->tm_sec = bcd2bin(buf[RTC_ADDR_SEC]);
+ time->tm_min = bcd2bin(buf[RTC_ADDR_MIN]);
+ time->tm_hour = bcd2bin(buf[RTC_ADDR_HOUR]);
+ time->tm_wday = buf[RTC_ADDR_DAY] - 1;
+ time->tm_mday = bcd2bin(buf[RTC_ADDR_DATE]);
+ time->tm_mon = bcd2bin(buf[RTC_ADDR_MON]) - 1;
+ time->tm_year = bcd2bin(buf[RTC_ADDR_YEAR]) + 100;
+
+ /* Time may not be set */
+ return rtc_valid_tm(time);
}
-static inline void ds1302_clock(void)
-{
- set_dp(get_dp() | RTC_SCLK); /* clock high */
- set_dp(get_dp() & ~RTC_SCLK); /* clock low */
-}
-
-static inline void ds1302_start(void)
-{
- set_dp(get_dp() | RTC_RESET);
-}
-
-static inline void ds1302_stop(void)
-{
- set_dp(get_dp() & ~RTC_RESET);
-}
-
-static inline void ds1302_txbit(int bit)
-{
- set_dp((get_dp() & ~RTC_IODATA) | (bit ? RTC_IODATA : 0));
-}
-
-static inline int ds1302_rxbit(void)
-{
- return !!(get_dp() & RTC_IODATA);
-}
-
-#else
-#error "Add support for your platform"
-#endif
+static struct rtc_class_ops ds1302_rtc_ops = {
+ .read_time = ds1302_rtc_get_time,
+ .set_time = ds1302_rtc_set_time,
+};
-static void ds1302_sendbits(unsigned int val)
+static int ds1302_probe(struct spi_device *spi)
{
- int i;
-
- ds1302_set_tx();
-
- for (i = 8; (i); i--, val >>= 1) {
- ds1302_txbit(val & 0x1);
- ds1302_clock();
+ struct rtc_device *rtc;
+ u8 addr;
+ u8 buf[4];
+ u8 *bp = buf;
+ int status;
+
+ /* Sanity check board setup data. This may be hooked up
+ * in 3wire mode, but we don't care. Note that unless
+ * there's an inverter in place, this needs SPI_CS_HIGH!
+ */
+ if (spi->bits_per_word && (spi->bits_per_word != 8)) {
+ dev_err(&spi->dev, "bad word length\n");
+ return -EINVAL;
+ } else if (spi->max_speed_hz > 2000000) {
+ dev_err(&spi->dev, "speed is too high\n");
+ return -EINVAL;
+ } else if (spi->mode & SPI_CPHA) {
+ dev_err(&spi->dev, "bad mode\n");
+ return -EINVAL;
}
-}
-
-static unsigned int ds1302_recvbits(void)
-{
- unsigned int val;
- int i;
-
- ds1302_set_rx();
- for (i = 0, val = 0; (i < 8); i++) {
- val |= (ds1302_rxbit() << i);
- ds1302_clock();
+ addr = RTC_ADDR_CTRL << 1 | RTC_CMD_READ;
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register read error %d\n",
+ status);
+ return status;
}
- return val;
-}
-
-static unsigned int ds1302_readbyte(unsigned int addr)
-{
- unsigned int val;
-
- ds1302_reset();
-
- ds1302_start();
- ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_READ);
- val = ds1302_recvbits();
- ds1302_stop();
-
- return val;
-}
-
-static void ds1302_writebyte(unsigned int addr, unsigned int val)
-{
- ds1302_reset();
-
- ds1302_start();
- ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_WRITE);
- ds1302_sendbits(val);
- ds1302_stop();
-}
-
-static int ds1302_rtc_read_time(struct device *dev, struct rtc_time *tm)
-{
- tm->tm_sec = bcd2bin(ds1302_readbyte(RTC_ADDR_SEC));
- tm->tm_min = bcd2bin(ds1302_readbyte(RTC_ADDR_MIN));
- tm->tm_hour = bcd2bin(ds1302_readbyte(RTC_ADDR_HOUR));
- tm->tm_wday = bcd2bin(ds1302_readbyte(RTC_ADDR_DAY));
- tm->tm_mday = bcd2bin(ds1302_readbyte(RTC_ADDR_DATE));
- tm->tm_mon = bcd2bin(ds1302_readbyte(RTC_ADDR_MON)) - 1;
- tm->tm_year = bcd2bin(ds1302_readbyte(RTC_ADDR_YEAR));
-
- if (tm->tm_year < 70)
- tm->tm_year += 100;
-
- dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
- "mday=%d, mon=%d, year=%d, wday=%d\n",
- __func__,
- tm->tm_sec, tm->tm_min, tm->tm_hour,
- tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
-
- return rtc_valid_tm(tm);
-}
-
-static int ds1302_rtc_set_time(struct device *dev, struct rtc_time *tm)
-{
- ds1302_writebyte(RTC_ADDR_CTRL, RTC_CMD_WRITE_ENABLE);
- /* Stop RTC */
- ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) | 0x80);
-
- ds1302_writebyte(RTC_ADDR_SEC, bin2bcd(tm->tm_sec));
- ds1302_writebyte(RTC_ADDR_MIN, bin2bcd(tm->tm_min));
- ds1302_writebyte(RTC_ADDR_HOUR, bin2bcd(tm->tm_hour));
- ds1302_writebyte(RTC_ADDR_DAY, bin2bcd(tm->tm_wday));
- ds1302_writebyte(RTC_ADDR_DATE, bin2bcd(tm->tm_mday));
- ds1302_writebyte(RTC_ADDR_MON, bin2bcd(tm->tm_mon + 1));
- ds1302_writebyte(RTC_ADDR_YEAR, bin2bcd(tm->tm_year % 100));
+ if ((buf[0] & ~RTC_CMD_WRITE_DISABLE) != 0) {
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register read error %d\n",
+ status);
+ return status;
+ }
+
+ if ((buf[0] & ~RTC_CMD_WRITE_DISABLE) != 0) {
+ dev_err(&spi->dev, "junk in control register\n");
+ return -ENODEV;
+ }
+ }
+ if (buf[0] == 0) {
+ bp = buf;
+ *bp++ = RTC_ADDR_CTRL << 1 | RTC_CMD_WRITE;
+ *bp++ = RTC_CMD_WRITE_DISABLE;
+
+ status = spi_write_then_read(spi, buf, 2, NULL, 0);
+ if (status < 0) {
+ dev_err(&spi->dev, "control register write error %d\n",
+ status);
+ return status;
+ }
+
+ addr = RTC_ADDR_CTRL << 1 | RTC_CMD_READ;
+ status = spi_write_then_read(spi, &addr, sizeof(addr), buf, 1);
+ if (status < 0) {
+ dev_err(&spi->dev,
+ "error %d reading control register\n",
+ status);
+ return status;
+ }
+
+ if (buf[0] != RTC_CMD_WRITE_DISABLE) {
+ dev_err(&spi->dev, "failed to detect chip\n");
+ return -ENODEV;
+ }
+ }
- /* Start RTC */
- ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) & ~0x80);
+ spi_set_drvdata(spi, spi);
- ds1302_writebyte(RTC_ADDR_CTRL, RTC_CMD_WRITE_DISABLE);
+ rtc = devm_rtc_device_register(&spi->dev, "ds1302",
+ &ds1302_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc)) {
+ status = PTR_ERR(rtc);
+ dev_err(&spi->dev, "error %d registering rtc\n", status);
+ return status;
+ }
return 0;
}
-static int ds1302_rtc_ioctl(struct device *dev, unsigned int cmd,
- unsigned long arg)
+static int ds1302_remove(struct spi_device *spi)
{
- switch (cmd) {
-#ifdef RTC_SET_CHARGE
- case RTC_SET_CHARGE:
- {
- int tcs_val;
-
- if (copy_from_user(&tcs_val, (int __user *)arg, sizeof(int)))
- return -EFAULT;
-
- ds1302_writebyte(RTC_ADDR_TCR, (0xa0 | tcs_val * 0xf));
- return 0;
- }
-#endif
- }
-
- return -ENOIOCTLCMD;
+ spi_set_drvdata(spi, NULL);
+ return 0;
}
-static struct rtc_class_ops ds1302_rtc_ops = {
- .read_time = ds1302_rtc_read_time,
- .set_time = ds1302_rtc_set_time,
- .ioctl = ds1302_rtc_ioctl,
+#ifdef CONFIG_OF
+static const struct of_device_id ds1302_dt_ids[] = {
+ { .compatible = "maxim,ds1302", },
+ { /* sentinel */ }
};
+MODULE_DEVICE_TABLE(of, ds1302_dt_ids);
+#endif
-static int __init ds1302_rtc_probe(struct platform_device *pdev)
-{
- struct rtc_device *rtc;
-
- if (ds1302_hw_init()) {
- dev_err(&pdev->dev, "Failed to init communication channel");
- return -EINVAL;
- }
-
- /* Reset */
- ds1302_reset();
-
- /* Write a magic value to the DS1302 RAM, and see if it sticks. */
- ds1302_writebyte(RTC_ADDR_RAM0, 0x42);
- if (ds1302_readbyte(RTC_ADDR_RAM0) != 0x42) {
- dev_err(&pdev->dev, "Failed to probe");
- return -ENODEV;
- }
-
- rtc = devm_rtc_device_register(&pdev->dev, "ds1302",
- &ds1302_rtc_ops, THIS_MODULE);
- if (IS_ERR(rtc))
- return PTR_ERR(rtc);
-
- platform_set_drvdata(pdev, rtc);
-
- return 0;
-}
-
-static struct platform_driver ds1302_platform_driver = {
- .driver = {
- .name = DRV_NAME,
- },
+static struct spi_driver ds1302_driver = {
+ .driver.name = "rtc-ds1302",
+ .driver.of_match_table = of_match_ptr(ds1302_dt_ids),
+ .probe = ds1302_probe,
+ .remove = ds1302_remove,
};
-module_platform_driver_probe(ds1302_platform_driver, ds1302_rtc_probe);
+module_spi_driver(ds1302_driver);
MODULE_DESCRIPTION("Dallas DS1302 RTC driver");
MODULE_VERSION(DRV_VERSION);
--
2.7.0
^ permalink raw reply related [flat|nested] 38+ messages in thread* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
2016-02-23 10:54 ` Sergei Ianovich
(?)
@ 2016-02-23 23:29 ` Rob Herring
-1 siblings, 0 replies; 38+ messages in thread
From: Rob Herring @ 2016-02-23 23:29 UTC (permalink / raw)
To: Sergei Ianovich
Cc: linux-kernel, Alexandre Belloni, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM
On Tue, Feb 23, 2016 at 01:54:57PM +0300, Sergei Ianovich wrote:
> DS1302 is half-duplex SPI device. The driver respects this fact now.
>
> Pin configurations should be implemented using SPI subsystem.
>
> Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
> CC: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> CC: Rob Herring <robh@kernel.org>
>
> v6..v7
> * change binding and doc file names
>
> v5..v6
> * rewrite the driver as an SPI slave device
> * use "maxim" for vendor name per Kconfig
> * stop changing device RAM in device presence test
> * only return time from device if valid
> * use burst mode for reading/writing time
> * dropped charging control. I cannot test it, and it looks broken
>
> v4..v5
> * drop THIS_MODULE from struct platform driver
> * use "dallas" for vendor name per vendor-prefixes.txt
>
> v3..v4
> * move DTS bindings to a different patch
>
> v2..v3
> * use usleep_range instead of custom nsleep
> * number change (07/16 -> 09/21)
>
> v0..v2
> * use device tree
> * use devm helpers where possible
> ---
> .../devicetree/bindings/rtc/maxim-ds1302.txt | 46 +++
Acked-by: Rob Herring <robh@kernel.org>
> drivers/rtc/Kconfig | 15 +-
> drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
> 3 files changed, 212 insertions(+), 197 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
@ 2016-02-23 23:29 ` Rob Herring
0 siblings, 0 replies; 38+ messages in thread
From: Rob Herring @ 2016-02-23 23:29 UTC (permalink / raw)
To: Sergei Ianovich
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA, Alexandre Belloni,
Pawel Moll, Mark Rutland, Ian Campbell, Kumar Gala,
Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM
On Tue, Feb 23, 2016 at 01:54:57PM +0300, Sergei Ianovich wrote:
> DS1302 is half-duplex SPI device. The driver respects this fact now.
>
> Pin configurations should be implemented using SPI subsystem.
>
> Signed-off-by: Sergei Ianovich <ynvich-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> CC: Alexandre Belloni <alexandre.belloni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> CC: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
>
> v6..v7
> * change binding and doc file names
>
> v5..v6
> * rewrite the driver as an SPI slave device
> * use "maxim" for vendor name per Kconfig
> * stop changing device RAM in device presence test
> * only return time from device if valid
> * use burst mode for reading/writing time
> * dropped charging control. I cannot test it, and it looks broken
>
> v4..v5
> * drop THIS_MODULE from struct platform driver
> * use "dallas" for vendor name per vendor-prefixes.txt
>
> v3..v4
> * move DTS bindings to a different patch
>
> v2..v3
> * use usleep_range instead of custom nsleep
> * number change (07/16 -> 09/21)
>
> v0..v2
> * use device tree
> * use devm helpers where possible
> ---
> .../devicetree/bindings/rtc/maxim-ds1302.txt | 46 +++
Acked-by: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> drivers/rtc/Kconfig | 15 +-
> drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
> 3 files changed, 212 insertions(+), 197 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
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^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
@ 2016-02-23 23:29 ` Rob Herring
0 siblings, 0 replies; 38+ messages in thread
From: Rob Herring @ 2016-02-23 23:29 UTC (permalink / raw)
To: Sergei Ianovich
Cc: linux-kernel, Alexandre Belloni, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM
On Tue, Feb 23, 2016 at 01:54:57PM +0300, Sergei Ianovich wrote:
> DS1302 is half-duplex SPI device. The driver respects this fact now.
>
> Pin configurations should be implemented using SPI subsystem.
>
> Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
> CC: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> CC: Rob Herring <robh@kernel.org>
>
> v6..v7
> * change binding and doc file names
>
> v5..v6
> * rewrite the driver as an SPI slave device
> * use "maxim" for vendor name per Kconfig
> * stop changing device RAM in device presence test
> * only return time from device if valid
> * use burst mode for reading/writing time
> * dropped charging control. I cannot test it, and it looks broken
>
> v4..v5
> * drop THIS_MODULE from struct platform driver
> * use "dallas" for vendor name per vendor-prefixes.txt
>
> v3..v4
> * move DTS bindings to a different patch
>
> v2..v3
> * use usleep_range instead of custom nsleep
> * number change (07/16 -> 09/21)
>
> v0..v2
> * use device tree
> * use devm helpers where possible
> ---
> .../devicetree/bindings/rtc/maxim-ds1302.txt | 46 +++
Acked-by: Rob Herring <robh@kernel.org>
> drivers/rtc/Kconfig | 15 +-
> drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
> 3 files changed, 212 insertions(+), 197 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
2016-02-23 10:54 ` Sergei Ianovich
(?)
@ 2016-03-15 0:18 ` Alexandre Belloni
-1 siblings, 0 replies; 38+ messages in thread
From: Alexandre Belloni @ 2016-03-15 0:18 UTC (permalink / raw)
To: Sergei Ianovich, Yoshinori Sato, Rich Felker
Cc: linux-kernel, Rob Herring, Rob Herring, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM, linux-sh
Hi,
Thank you for your work!
On 23/02/2016 at 13:54:57 +0300, Sergei Ianovich wrote :
> -#ifdef CONFIG_SH_SECUREEDGE5410
> -#include <asm/rtc.h>
> -#include <mach/secureedge5410.h>
> -
> -#define RTC_RESET 0x1000
> -#define RTC_IODATA 0x0800
> -#define RTC_SCLK 0x0400
> -
> -#define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00)
> -#define get_dp() SECUREEDGE_READ_IOPORT()
> -#define ds1302_set_tx()
> -#define ds1302_set_rx()
> -
I would like to have a solution for secureedge5410 even if it is
untested. Else, we are breaking an existing platform without any
solution.
I've put the sh maintainers in copy, maybe they have an opinion. Else
I'll let your patch sit in linux-next for the next cycle.
I have further cleanups in that driver but they can probably be done
later.
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
@ 2016-03-15 0:18 ` Alexandre Belloni
0 siblings, 0 replies; 38+ messages in thread
From: Alexandre Belloni @ 2016-03-15 0:18 UTC (permalink / raw)
To: Sergei Ianovich, Yoshinori Sato, Rich Felker
Cc: linux-kernel, Rob Herring, Rob Herring, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM, linux-sh
Hi,
Thank you for your work!
On 23/02/2016 at 13:54:57 +0300, Sergei Ianovich wrote :
> -#ifdef CONFIG_SH_SECUREEDGE5410
> -#include <asm/rtc.h>
> -#include <mach/secureedge5410.h>
> -
> -#define RTC_RESET 0x1000
> -#define RTC_IODATA 0x0800
> -#define RTC_SCLK 0x0400
> -
> -#define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00)
> -#define get_dp() SECUREEDGE_READ_IOPORT()
> -#define ds1302_set_tx()
> -#define ds1302_set_rx()
> -
I would like to have a solution for secureedge5410 even if it is
untested. Else, we are breaking an existing platform without any
solution.
I've put the sh maintainers in copy, maybe they have an opinion. Else
I'll let your patch sit in linux-next for the next cycle.
I have further cleanups in that driver but they can probably be done
later.
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
@ 2016-03-15 0:18 ` Alexandre Belloni
0 siblings, 0 replies; 38+ messages in thread
From: Alexandre Belloni @ 2016-03-15 0:18 UTC (permalink / raw)
To: Sergei Ianovich, Yoshinori Sato, Rich Felker
Cc: linux-kernel, Rob Herring, Rob Herring, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM, linux-sh
Hi,
Thank you for your work!
On 23/02/2016 at 13:54:57 +0300, Sergei Ianovich wrote :
> -#ifdef CONFIG_SH_SECUREEDGE5410
> -#include <asm/rtc.h>
> -#include <mach/secureedge5410.h>
> -
> -#define RTC_RESET 0x1000
> -#define RTC_IODATA 0x0800
> -#define RTC_SCLK 0x0400
> -
> -#define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00)
> -#define get_dp() SECUREEDGE_READ_IOPORT()
> -#define ds1302_set_tx()
> -#define ds1302_set_rx()
> -
I would like to have a solution for secureedge5410 even if it is
untested. Else, we are breaking an existing platform without any
solution.
I've put the sh maintainers in copy, maybe they have an opinion. Else
I'll let your patch sit in linux-next for the next cycle.
I have further cleanups in that driver but they can probably be done
later.
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
2016-03-15 0:18 ` Alexandre Belloni
(?)
@ 2016-03-18 10:38 ` Sergei Ianovich
-1 siblings, 0 replies; 38+ messages in thread
From: Sergei Ianovich @ 2016-03-18 10:38 UTC (permalink / raw)
To: Alexandre Belloni, Yoshinori Sato, Rich Felker
Cc: linux-kernel, Rob Herring, Rob Herring, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM, linux-sh
On Tue, 2016-03-15 at 01:18 +0100, Alexandre Belloni wrote:
> I would like to have a solution for secureedge5410 even if it is
> untested. Else, we are breaking an existing platform without any
> solution.
>
> I've put the sh maintainers in copy, maybe they have an opinion. Else
> I'll let your patch sit in linux-next for the next cycle.
secureedge5410 will need an SPI host driver. The driver will be similar
to the one I did for lp8841. I can make a clone for secureedge5410, but
I cannot test it.
The only reason, I didn't file the patch for secureedge5410, is I
thought SPI people won't accept an untested patch.
^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
@ 2016-03-18 10:38 ` Sergei Ianovich
0 siblings, 0 replies; 38+ messages in thread
From: Sergei Ianovich @ 2016-03-18 10:38 UTC (permalink / raw)
To: Alexandre Belloni, Yoshinori Sato, Rich Felker
Cc: linux-kernel, Rob Herring, Rob Herring, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM, linux-sh
On Tue, 2016-03-15 at 01:18 +0100, Alexandre Belloni wrote:
> I would like to have a solution for secureedge5410 even if it is
> untested. Else, we are breaking an existing platform without any
> solution.
>
> I've put the sh maintainers in copy, maybe they have an opinion. Else
> I'll let your patch sit in linux-next for the next cycle.
secureedge5410 will need an SPI host driver. The driver will be similar
to the one I did for lp8841. I can make a clone for secureedge5410, but
I cannot test it.
The only reason, I didn't file the patch for secureedge5410, is I
thought SPI people won't accept an untested patch.
^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
@ 2016-03-18 10:38 ` Sergei Ianovich
0 siblings, 0 replies; 38+ messages in thread
From: Sergei Ianovich @ 2016-03-18 10:38 UTC (permalink / raw)
To: Alexandre Belloni, Yoshinori Sato, Rich Felker
Cc: linux-kernel, Rob Herring, Rob Herring, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM, linux-sh
On Tue, 2016-03-15 at 01:18 +0100, Alexandre Belloni wrote:
> I would like to have a solution for secureedge5410 even if it is
> untested. Else, we are breaking an existing platform without any
> solution.
>
> I've put the sh maintainers in copy, maybe they have an opinion. Else
> I'll let your patch sit in linux-next for the next cycle.
secureedge5410 will need an SPI host driver. The driver will be similar
to the one I did for lp8841. I can make a clone for secureedge5410, but
I cannot test it.
The only reason, I didn't file the patch for secureedge5410, is I
thought SPI people won't accept an untested patch.
^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
2016-02-23 10:54 ` Sergei Ianovich
(?)
@ 2016-03-28 20:57 ` Alexandre Belloni
-1 siblings, 0 replies; 38+ messages in thread
From: Alexandre Belloni @ 2016-03-28 20:57 UTC (permalink / raw)
To: Sergei Ianovich
Cc: linux-kernel, Rob Herring, Rob Herring, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM
On 23/02/2016 at 13:54:57 +0300, Sergei Ianovich wrote :
> DS1302 is half-duplex SPI device. The driver respects this fact now.
>
> Pin configurations should be implemented using SPI subsystem.
>
> Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
> CC: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> CC: Rob Herring <robh@kernel.org>
>
> v6..v7
> * change binding and doc file names
>
> v5..v6
> * rewrite the driver as an SPI slave device
> * use "maxim" for vendor name per Kconfig
> * stop changing device RAM in device presence test
> * only return time from device if valid
> * use burst mode for reading/writing time
> * dropped charging control. I cannot test it, and it looks broken
>
> v4..v5
> * drop THIS_MODULE from struct platform driver
> * use "dallas" for vendor name per vendor-prefixes.txt
>
> v3..v4
> * move DTS bindings to a different patch
>
> v2..v3
> * use usleep_range instead of custom nsleep
> * number change (07/16 -> 09/21)
>
> v0..v2
> * use device tree
> * use devm helpers where possible
> ---
> .../devicetree/bindings/rtc/maxim-ds1302.txt | 46 +++
> drivers/rtc/Kconfig | 15 +-
> drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
> 3 files changed, 212 insertions(+), 197 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
>
Applied, thanks.
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
@ 2016-03-28 20:57 ` Alexandre Belloni
0 siblings, 0 replies; 38+ messages in thread
From: Alexandre Belloni @ 2016-03-28 20:57 UTC (permalink / raw)
To: Sergei Ianovich
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA, Rob Herring, Rob Herring,
Pawel Moll, Mark Rutland, Ian Campbell, Kumar Gala,
Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM
On 23/02/2016 at 13:54:57 +0300, Sergei Ianovich wrote :
> DS1302 is half-duplex SPI device. The driver respects this fact now.
>
> Pin configurations should be implemented using SPI subsystem.
>
> Signed-off-by: Sergei Ianovich <ynvich-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> CC: Alexandre Belloni <alexandre.belloni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> CC: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
>
> v6..v7
> * change binding and doc file names
>
> v5..v6
> * rewrite the driver as an SPI slave device
> * use "maxim" for vendor name per Kconfig
> * stop changing device RAM in device presence test
> * only return time from device if valid
> * use burst mode for reading/writing time
> * dropped charging control. I cannot test it, and it looks broken
>
> v4..v5
> * drop THIS_MODULE from struct platform driver
> * use "dallas" for vendor name per vendor-prefixes.txt
>
> v3..v4
> * move DTS bindings to a different patch
>
> v2..v3
> * use usleep_range instead of custom nsleep
> * number change (07/16 -> 09/21)
>
> v0..v2
> * use device tree
> * use devm helpers where possible
> ---
> .../devicetree/bindings/rtc/maxim-ds1302.txt | 46 +++
> drivers/rtc/Kconfig | 15 +-
> drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
> 3 files changed, 212 insertions(+), 197 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
>
Applied, thanks.
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
--
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^ permalink raw reply [flat|nested] 38+ messages in thread
* Re: [PATCH v7] rtc: rewrite DS1302 using SPI
@ 2016-03-28 20:57 ` Alexandre Belloni
0 siblings, 0 replies; 38+ messages in thread
From: Alexandre Belloni @ 2016-03-28 20:57 UTC (permalink / raw)
To: Sergei Ianovich
Cc: linux-kernel, Rob Herring, Rob Herring, Pawel Moll, Mark Rutland,
Ian Campbell, Kumar Gala, Alessandro Zummo,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
open list:REAL TIME CLOCK RTC SUBSYSTEM
On 23/02/2016 at 13:54:57 +0300, Sergei Ianovich wrote :
> DS1302 is half-duplex SPI device. The driver respects this fact now.
>
> Pin configurations should be implemented using SPI subsystem.
>
> Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
> CC: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> CC: Rob Herring <robh@kernel.org>
>
> v6..v7
> * change binding and doc file names
>
> v5..v6
> * rewrite the driver as an SPI slave device
> * use "maxim" for vendor name per Kconfig
> * stop changing device RAM in device presence test
> * only return time from device if valid
> * use burst mode for reading/writing time
> * dropped charging control. I cannot test it, and it looks broken
>
> v4..v5
> * drop THIS_MODULE from struct platform driver
> * use "dallas" for vendor name per vendor-prefixes.txt
>
> v3..v4
> * move DTS bindings to a different patch
>
> v2..v3
> * use usleep_range instead of custom nsleep
> * number change (07/16 -> 09/21)
>
> v0..v2
> * use device tree
> * use devm helpers where possible
> ---
> .../devicetree/bindings/rtc/maxim-ds1302.txt | 46 +++
> drivers/rtc/Kconfig | 15 +-
> drivers/rtc/rtc-ds1302.c | 348 ++++++++++-----------
> 3 files changed, 212 insertions(+), 197 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/rtc/maxim-ds1302.txt
>
Applied, thanks.
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
^ permalink raw reply [flat|nested] 38+ messages in thread