* + gpio-add-driver-for-max7300-i2c-gpio-extender.patch added to -mm tree
@ 2009-11-20 23:34 akpm
0 siblings, 0 replies; 2+ messages in thread
From: akpm @ 2009-11-20 23:34 UTC (permalink / raw)
To: mm-commits; +Cc: w.sang, avorontsov, dbrownell, j.beisert, khali
The patch titled
gpio: add driver for MAX7300 I2C GPIO extender
has been added to the -mm tree. Its filename is
gpio-add-driver-for-max7300-i2c-gpio-extender.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: gpio: add driver for MAX7300 I2C GPIO extender
From: Wolfram Sang <w.sang@pengutronix.de>
Add the MAX7300-I2C variant to the MAX7301-SPI version. They share most
parts of the driver (i.e. the logic) and the read/write-register
functions get encapsulated. It is thus possible to use both variants
simultaneously. (This is the outcome of an experiment how to combine I2C
and SPI into one driver.)
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Juergen Beisert <j.beisert@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
drivers/gpio/Kconfig | 27 ++-
drivers/gpio/max7301.c | 307 +++++++++++++++++++++++++--------------
2 files changed, 225 insertions(+), 109 deletions(-)
diff -puN drivers/gpio/Kconfig~gpio-add-driver-for-max7300-i2c-gpio-extender drivers/gpio/Kconfig
--- a/drivers/gpio/Kconfig~gpio-add-driver-for-max7300-i2c-gpio-extender
+++ a/drivers/gpio/Kconfig
@@ -65,6 +65,27 @@ config GPIO_SYSFS
# put expanders in the right section, in alphabetical order
+comment "GPIO expanders for multiple busses"
+
+config GPIO_MAX7301
+ tristate "Maxim MAX730x GPIO expander"
+ depends on I2C || SPI_MASTER
+ help
+ GPIO driver for Maxim MAX7300/7301 GPIO expanders.
+ Also select which bus you want to use.
+
+if GPIO_MAX7301
+config GPIO_MAX7301_I2C
+ bool "I2C support (for MAX7300)"
+ depends on I2C
+ default y
+
+config GPIO_MAX7301_SPI
+ bool "SPI support (for MAX7301)"
+ depends on SPI_MASTER
+ default y
+endif
+
comment "Memory mapped GPIO expanders:"
config GPIO_PL061
@@ -214,12 +235,6 @@ config GPIO_TIMBERDALE
comment "SPI GPIO expanders:"
-config GPIO_MAX7301
- tristate "Maxim MAX7301 GPIO expander"
- depends on SPI_MASTER
- help
- gpio driver for Maxim MAX7301 SPI GPIO expander.
-
config GPIO_MCP23S08
tristate "Microchip MCP23S08 I/O expander"
depends on SPI_MASTER
diff -puN drivers/gpio/max7301.c~gpio-add-driver-for-max7300-i2c-gpio-extender drivers/gpio/max7301.c
--- a/drivers/gpio/max7301.c~gpio-add-driver-for-max7300-i2c-gpio-extender
+++ a/drivers/gpio/max7301.c
@@ -3,6 +3,7 @@
*
* Copyright (C) 2006 Juergen Beisert, Pengutronix
* Copyright (C) 2008 Guennadi Liakhovetski, Pengutronix
+ * Copyright (C) 2009 Wolfram Sang, Pengutronix
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
@@ -34,12 +35,11 @@
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
+#include <linux/i2c.h>
#include <linux/spi/spi.h>
#include <linux/spi/max7301.h>
#include <linux/gpio.h>
-#define DRIVER_NAME "max7301"
-
/*
* Pin configurations, see MAX7301 datasheet page 6
*/
@@ -50,7 +50,6 @@
#define PIN_NUMBER 28
-
/*
* Some registers must be read back to modify.
* To save time we cache them here in memory
@@ -60,62 +59,21 @@ struct max7301 {
u8 port_config[8]; /* field 0 is unused */
u32 out_level; /* cached output levels */
struct gpio_chip chip;
- struct spi_device *spi;
+ struct device *dev;
+ int (*write)(struct device *dev, unsigned int reg, unsigned int val);
+ int (*read)(struct device *dev, unsigned int reg);
};
-/**
- * max7301_write - Write a new register content
- * @spi: The SPI device
- * @reg: Register offset
- * @val: Value to write
- *
- * A write to the MAX7301 means one message with one transfer
- *
- * Returns 0 if successful or a negative value on error
- */
-static int max7301_write(struct spi_device *spi, unsigned int reg, unsigned int val)
-{
- u16 word = ((reg & 0x7F) << 8) | (val & 0xFF);
- return spi_write(spi, (const u8 *)&word, sizeof(word));
-}
-
-/**
- * max7301_read - Read back register content
- * @spi: The SPI device
- * @reg: Register offset
- *
- * A read from the MAX7301 means two transfers; here, one message each
- *
- * Returns positive 8 bit value from device if successful or a
- * negative value on error
- */
-static int max7301_read(struct spi_device *spi, unsigned int reg)
-{
- int ret;
- u16 word;
-
- word = 0x8000 | (reg << 8);
- ret = spi_write(spi, (const u8 *)&word, sizeof(word));
- if (ret)
- return ret;
- /*
- * This relies on the fact, that a transfer with NULL tx_buf shifts out
- * zero bytes (=NOOP for MAX7301)
- */
- ret = spi_read(spi, (u8 *)&word, sizeof(word));
- if (ret)
- return ret;
- return word & 0xff;
-}
-
static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct max7301 *ts = container_of(chip, struct max7301, chip);
u8 *config;
+ u8 offset_bits;
int ret;
/* First 4 pins are unused in the controller */
offset += 4;
+ offset_bits = (offset & 3) << 1;
config = &ts->port_config[offset >> 2];
@@ -123,9 +81,10 @@ static int max7301_direction_input(struc
/* Standard GPIO API doesn't support pull-ups, has to be extended.
* Hard-coding no pollup for now. */
- *config = (*config & ~(3 << (offset & 3))) | (1 << (offset & 3));
+ *config = (*config & ~(PIN_CONFIG_MASK << offset_bits))
+ | (PIN_CONFIG_IN_WO_PULLUP << offset_bits);
- ret = max7301_write(ts->spi, 0x08 + (offset >> 2), *config);
+ ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);
mutex_unlock(&ts->lock);
@@ -136,10 +95,10 @@ static int __max7301_set(struct max7301
{
if (value) {
ts->out_level |= 1 << offset;
- return max7301_write(ts->spi, 0x20 + offset, 0x01);
+ return ts->write(ts->dev, 0x20 + offset, 0x01);
} else {
ts->out_level &= ~(1 << offset);
- return max7301_write(ts->spi, 0x20 + offset, 0x00);
+ return ts->write(ts->dev, 0x20 + offset, 0x00);
}
}
@@ -148,21 +107,24 @@ static int max7301_direction_output(stru
{
struct max7301 *ts = container_of(chip, struct max7301, chip);
u8 *config;
+ u8 offset_bits;
int ret;
/* First 4 pins are unused in the controller */
offset += 4;
+ offset_bits = (offset & 3) << 1;
config = &ts->port_config[offset >> 2];
mutex_lock(&ts->lock);
- *config = (*config & ~(3 << (offset & 3))) | (1 << (offset & 3));
+ *config = (*config & ~(PIN_CONFIG_MASK << offset_bits))
+ | (PIN_CONFIG_OUT << offset_bits);
ret = __max7301_set(ts, offset, value);
if (!ret)
- ret = max7301_write(ts->spi, 0x08 + (offset >> 2), *config);
+ ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);
mutex_unlock(&ts->lock);
@@ -179,17 +141,18 @@ static int max7301_get(struct gpio_chip
mutex_lock(&ts->lock);
- config = (ts->port_config[offset >> 2] >> ((offset & 3) * 2)) & 3;
+ config = (ts->port_config[offset >> 2] >> ((offset & 3) << 1))
+ & PIN_CONFIG_MASK;
switch (config) {
- case 1:
+ case PIN_CONFIG_OUT:
/* Output: return cached level */
level = !!(ts->out_level & (1 << offset));
break;
- case 2:
- case 3:
+ case PIN_CONFIG_IN_WO_PULLUP:
+ case PIN_CONFIG_IN_PULLUP:
/* Input: read out */
- level = max7301_read(ts->spi, 0x20 + offset) & 0x01;
+ level = ts->read(ts->dev, 0x20 + offset) & 0x01;
}
mutex_unlock(&ts->lock);
@@ -210,41 +173,25 @@ static void max7301_set(struct gpio_chip
mutex_unlock(&ts->lock);
}
-static int __devinit max7301_probe(struct spi_device *spi)
+static int __devinit __max7301_probe(struct max7301 *ts)
{
- struct max7301 *ts;
+ struct device *dev = ts->dev;
struct max7301_platform_data *pdata;
int i, ret;
- pdata = spi->dev.platform_data;
+ pdata = dev->platform_data;
if (!pdata || !pdata->base) {
- dev_dbg(&spi->dev, "incorrect or missing platform data\n");
+ dev_err(dev, "incorrect or missing platform data\n");
return -EINVAL;
}
- /*
- * bits_per_word cannot be configured in platform data
- */
- spi->bits_per_word = 16;
-
- ret = spi_setup(spi);
- if (ret < 0)
- return ret;
-
- ts = kzalloc(sizeof(struct max7301), GFP_KERNEL);
- if (!ts)
- return -ENOMEM;
-
mutex_init(&ts->lock);
-
- dev_set_drvdata(&spi->dev, ts);
+ dev_set_drvdata(dev, ts);
/* Power up the chip and disable IRQ output */
- max7301_write(spi, 0x04, 0x01);
-
- ts->spi = spi;
+ ts->write(dev, 0x04, 0x01);
- ts->chip.label = DRIVER_NAME,
+ ts->chip.label = dev->driver->name;
ts->chip.direction_input = max7301_direction_input;
ts->chip.get = max7301_get;
@@ -254,7 +201,7 @@ static int __devinit max7301_probe(struc
ts->chip.base = pdata->base;
ts->chip.ngpio = PIN_NUMBER;
ts->chip.can_sleep = 1;
- ts->chip.dev = &spi->dev;
+ ts->chip.dev = dev;
ts->chip.owner = THIS_MODULE;
/*
@@ -264,7 +211,7 @@ static int __devinit max7301_probe(struc
for (i = 1; i < 8; i++) {
int j;
/* 0xAA means input with internal pullup disabled */
- max7301_write(spi, 0x08 + i, 0xAA);
+ ts->write(dev, 0x08 + i, 0xAA);
ts->port_config[i] = 0xAA;
for (j = 0; j < 4; j++) {
int offset = (i - 1) * 4 + j;
@@ -281,49 +228,203 @@ static int __devinit max7301_probe(struc
return ret;
exit_destroy:
- dev_set_drvdata(&spi->dev, NULL);
+ dev_set_drvdata(dev, NULL);
mutex_destroy(&ts->lock);
- kfree(ts);
return ret;
}
-static int __devexit max7301_remove(struct spi_device *spi)
+static int __devexit __max7301_remove(struct device *dev)
{
- struct max7301 *ts;
+ struct max7301 *ts = dev_get_drvdata(dev);
int ret;
- ts = dev_get_drvdata(&spi->dev);
if (ts == NULL)
return -ENODEV;
- dev_set_drvdata(&spi->dev, NULL);
+ dev_set_drvdata(dev, NULL);
/* Power down the chip and disable IRQ output */
- max7301_write(spi, 0x04, 0x00);
+ ts->write(dev, 0x04, 0x00);
ret = gpiochip_remove(&ts->chip);
if (!ret) {
mutex_destroy(&ts->lock);
kfree(ts);
} else
- dev_err(&spi->dev, "Failed to remove the GPIO controller: %d\n",
- ret);
+ dev_err(dev, "Failed to remove GPIO controller: %d\n", ret);
+
+ return ret;
+}
+
+#ifdef CONFIG_GPIO_MAX7301_SPI
+
+/* A write to the MAX7301 means one message with one transfer */
+static int max7301_spi_write(struct device *dev, unsigned int reg,
+ unsigned int val)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ u16 word = ((reg & 0x7F) << 8) | (val & 0xFF);
+
+ return spi_write(spi, (const u8 *)&word, sizeof(word));
+}
+
+/* A read from the MAX7301 means two transfers; here, one message each */
+
+static int max7301_spi_read(struct device *dev, unsigned int reg)
+{
+ int ret;
+ u16 word;
+ struct spi_device *spi = to_spi_device(dev);
+
+ word = 0x8000 | (reg << 8);
+ ret = spi_write(spi, (const u8 *)&word, sizeof(word));
+ if (ret)
+ return ret;
+ /*
+ * This relies on the fact, that a transfer with NULL tx_buf shifts out
+ * zero bytes (=NOOP for MAX7301)
+ */
+ ret = spi_read(spi, (u8 *)&word, sizeof(word));
+ if (ret)
+ return ret;
+ return word & 0xff;
+}
+
+static int __devinit max7301_probe(struct spi_device *spi)
+{
+ struct max7301 *ts;
+ int ret;
+
+ /* bits_per_word cannot be configured in platform data */
+ spi->bits_per_word = 16;
+ ret = spi_setup(spi);
+ if (ret < 0)
+ return ret;
+
+ ts = kzalloc(sizeof(struct max7301), GFP_KERNEL);
+ if (!ts)
+ return -ENOMEM;
+
+ ts->read = max7301_spi_read;
+ ts->write = max7301_spi_write;
+ ts->dev = &spi->dev;
+ ret = __max7301_probe(ts);
+ if (ret)
+ kfree(ts);
return ret;
}
+static int __devexit max7301_remove(struct spi_device *spi)
+{
+ return __max7301_remove(&spi->dev);
+}
+
+static const struct spi_device_id max7301_id[] = {
+ { "max7301", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, max7301_id);
+
static struct spi_driver max7301_driver = {
.driver = {
- .name = DRIVER_NAME,
- .owner = THIS_MODULE,
+ .name = "max7301",
+ .owner = THIS_MODULE,
+ },
+ .probe = max7301_probe,
+ .remove = __devexit_p(max7301_remove),
+ .id_table = max7301_id,
+};
+
+#define max7301_add_driver(drv) spi_register_driver(drv)
+#define max7301_del_driver(drv) spi_unregister_driver(drv)
+#else
+#define max7301_add_driver(drv) (0)
+#define max7301_del_driver(drv) do { } while (0)
+#endif /* CONFIG_GPIO_MAX7301_SPI */
+
+#ifdef CONFIG_GPIO_MAX7301_I2C
+
+static int max7301_i2c_write(struct device *dev, unsigned int reg,
+ unsigned int val)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+
+ return i2c_smbus_write_byte_data(client, reg, val);
+}
+
+static int max7301_i2c_read(struct device *dev, unsigned int reg)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+
+ return i2c_smbus_read_byte_data(client, reg);
+}
+
+static int __devinit max7300_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct max7301 *ts;
+ int ret;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_BYTE_DATA))
+ return -EIO;
+
+ ts = kzalloc(sizeof(struct max7301), GFP_KERNEL);
+ if (!ts)
+ return -ENOMEM;
+
+ ts->read = max7301_i2c_read;
+ ts->write = max7301_i2c_write;
+ ts->dev = &client->dev;
+
+ ret = __max7301_probe(ts);
+ if (ret)
+ kfree(ts);
+ return ret;
+}
+
+static int __devexit max7300_remove(struct i2c_client *client)
+{
+ return __max7301_remove(&client->dev);
+}
+
+static const struct i2c_device_id max7300_id[] = {
+ { "max7300", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, max7300_id);
+
+static struct i2c_driver max7300_driver = {
+ .driver = {
+ .name = "max7300",
+ .owner = THIS_MODULE,
},
- .probe = max7301_probe,
- .remove = __devexit_p(max7301_remove),
+ .probe = max7300_probe,
+ .remove = __devexit_p(max7300_remove),
+ .id_table = max7300_id,
};
+#define max7300_add_driver(drv) i2c_add_driver(drv)
+#define max7300_del_driver(drv) i2c_del_driver(drv)
+#else
+#define max7300_add_driver(drv) (0)
+#define max7300_del_driver(drv) do { } while (0)
+#endif /* CONFIG_GPIO_MAX7301_I2C */
+
static int __init max7301_init(void)
{
- return spi_register_driver(&max7301_driver);
+ int ret;
+
+ ret = max7300_add_driver(&max7300_driver);
+ if (ret)
+ return ret;
+
+ ret = max7301_add_driver(&max7301_driver);
+ if (ret)
+ max7300_del_driver(&max7300_driver);
+
+ return ret;
}
/* register after spi postcore initcall and before
* subsys initcalls that may rely on these GPIOs
@@ -332,11 +433,11 @@ subsys_initcall(max7301_init);
static void __exit max7301_exit(void)
{
- spi_unregister_driver(&max7301_driver);
+ max7300_del_driver(&max7300_driver);
+ max7301_del_driver(&max7301_driver);
}
module_exit(max7301_exit);
-MODULE_AUTHOR("Juergen Beisert");
+MODULE_AUTHOR("Juergen Beisert, Wolfram Sang");
MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("MAX7301 SPI based GPIO-Expander");
-MODULE_ALIAS("spi:" DRIVER_NAME);
+MODULE_DESCRIPTION("MAX7300/1 based GPIO-Expander");
_
Patches currently in -mm which might be from w.sang@pengutronix.de are
linux-next.patch
scripts-get_maintainerpl-fix-non-with-git-blame-and-cleanups.patch
checkpatch-fix-false-positive-on-__initconst.patch
gpio-add-driver-for-max7300-i2c-gpio-extender.patch
^ permalink raw reply [flat|nested] 2+ messages in thread
* + gpio-add-driver-for-max7300-i2c-gpio-extender.patch added to -mm tree
@ 2009-12-16 21:57 akpm
0 siblings, 0 replies; 2+ messages in thread
From: akpm @ 2009-12-16 21:57 UTC (permalink / raw)
To: mm-commits; +Cc: w.sang, avorontsov, dbrownell, j.beisert, khali, randy.dunlap
The patch titled
] gpio: add driver for MAX7300 I2C GPIO extender
has been added to the -mm tree. Its filename is
gpio-add-driver-for-max7300-i2c-gpio-extender.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: ] gpio: add driver for MAX7300 I2C GPIO extender
From: Wolfram Sang <w.sang@pengutronix.de>
Done by factoring out the generic routines from MAX7301 into MAX730X and
adding wrappers for MAX7300 (I2C) and MAX7301 (SPI).
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Juergen Beisert <j.beisert@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
drivers/gpio/Kconfig | 13 +
drivers/gpio/Makefile | 2
drivers/gpio/max7300.c | 94 ++++++++++
drivers/gpio/max7301.c | 293 +++-------------------------------
drivers/gpio/max730x.c | 244 ++++++++++++++++++++++++++++
include/linux/spi/max7301.h | 18 ++
6 files changed, 404 insertions(+), 260 deletions(-)
diff -puN drivers/gpio/Kconfig~gpio-add-driver-for-max7300-i2c-gpio-extender drivers/gpio/Kconfig
--- a/drivers/gpio/Kconfig~gpio-add-driver-for-max7300-i2c-gpio-extender
+++ a/drivers/gpio/Kconfig
@@ -65,6 +65,9 @@ config GPIO_SYSFS
# put expanders in the right section, in alphabetical order
+config GPIO_MAX730X
+ tristate
+
comment "Memory mapped GPIO expanders:"
config GPIO_PL061
@@ -87,6 +90,13 @@ config GPIO_VR41XX
comment "I2C GPIO expanders:"
+config GPIO_MAX7300
+ tristate "Maxim MAX7300 GPIO expander"
+ depends on I2C
+ select GPIO_MAX730X
+ help
+ GPIO driver for Maxim MAX7301 I2C-based GPIO expander.
+
config GPIO_MAX732X
tristate "MAX7319, MAX7320-7327 I2C Port Expanders"
depends on I2C
@@ -217,8 +227,9 @@ comment "SPI GPIO expanders:"
config GPIO_MAX7301
tristate "Maxim MAX7301 GPIO expander"
depends on SPI_MASTER
+ select GPIO_MAX730X
help
- gpio driver for Maxim MAX7301 SPI GPIO expander.
+ GPIO driver for Maxim MAX7301 SPI-based GPIO expander.
config GPIO_MCP23S08
tristate "Microchip MCP23S08 I/O expander"
diff -puN drivers/gpio/Makefile~gpio-add-driver-for-max7300-i2c-gpio-extender drivers/gpio/Makefile
--- a/drivers/gpio/Makefile~gpio-add-driver-for-max7300-i2c-gpio-extender
+++ a/drivers/gpio/Makefile
@@ -6,6 +6,8 @@ obj-$(CONFIG_GPIOLIB) += gpiolib.o
obj-$(CONFIG_GPIO_ADP5520) += adp5520-gpio.o
obj-$(CONFIG_GPIO_LANGWELL) += langwell_gpio.o
+obj-$(CONFIG_GPIO_MAX730X) += max730x.o
+obj-$(CONFIG_GPIO_MAX7300) += max7300.o
obj-$(CONFIG_GPIO_MAX7301) += max7301.o
obj-$(CONFIG_GPIO_MAX732X) += max732x.o
obj-$(CONFIG_GPIO_MC33880) += mc33880.o
diff -puN /dev/null drivers/gpio/max7300.c
--- /dev/null
+++ a/drivers/gpio/max7300.c
@@ -0,0 +1,94 @@
+/*
+ * drivers/gpio/max7300.c
+ *
+ * Copyright (C) 2009 Wolfram Sang, Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Check max730x.c for further details.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/i2c.h>
+#include <linux/spi/max7301.h>
+
+static int max7300_i2c_write(struct device *dev, unsigned int reg,
+ unsigned int val)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+
+ return i2c_smbus_write_byte_data(client, reg, val);
+}
+
+static int max7300_i2c_read(struct device *dev, unsigned int reg)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+
+ return i2c_smbus_read_byte_data(client, reg);
+}
+
+static int __devinit max7300_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct max7301 *ts;
+ int ret;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_BYTE_DATA))
+ return -EIO;
+
+ ts = kzalloc(sizeof(struct max7301), GFP_KERNEL);
+ if (!ts)
+ return -ENOMEM;
+
+ ts->read = max7300_i2c_read;
+ ts->write = max7300_i2c_write;
+ ts->dev = &client->dev;
+
+ ret = __max730x_probe(ts);
+ if (ret)
+ kfree(ts);
+ return ret;
+}
+
+static int __devexit max7300_remove(struct i2c_client *client)
+{
+ return __max730x_remove(&client->dev);
+}
+
+static const struct i2c_device_id max7300_id[] = {
+ { "max7300", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, max7300_id);
+
+static struct i2c_driver max7300_driver = {
+ .driver = {
+ .name = "max7300",
+ .owner = THIS_MODULE,
+ },
+ .probe = max7300_probe,
+ .remove = __devexit_p(max7300_remove),
+ .id_table = max7300_id,
+};
+
+static int __init max7300_init(void)
+{
+ return i2c_add_driver(&max7300_driver);
+}
+subsys_initcall(max7300_init);
+
+static void __exit max7300_exit(void)
+{
+ i2c_del_driver(&max7300_driver);
+}
+module_exit(max7300_exit);
+
+MODULE_AUTHOR("Wolfram Sang");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MAX7300 GPIO-Expander");
diff -puN drivers/gpio/max7301.c~gpio-add-driver-for-max7300-i2c-gpio-extender drivers/gpio/max7301.c
--- a/drivers/gpio/max7301.c~gpio-add-driver-for-max7300-i2c-gpio-extender
+++ a/drivers/gpio/max7301.c
@@ -1,98 +1,41 @@
-/**
+/*
* drivers/gpio/max7301.c
*
* Copyright (C) 2006 Juergen Beisert, Pengutronix
* Copyright (C) 2008 Guennadi Liakhovetski, Pengutronix
+ * Copyright (C) 2009 Wolfram Sang, Pengutronix
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
- * The Maxim's MAX7301 device is an SPI driven GPIO expander. There are
- * 28 GPIOs. 8 of them can trigger an interrupt. See datasheet for more
- * details
- * Note:
- * - DIN must be stable at the rising edge of clock.
- * - when writing:
- * - always clock in 16 clocks at once
- * - at DIN: D15 first, D0 last
- * - D0..D7 = databyte, D8..D14 = commandbyte
- * - D15 = low -> write command
- * - when reading
- * - always clock in 16 clocks at once
- * - at DIN: D15 first, D0 last
- * - D0..D7 = dummy, D8..D14 = register address
- * - D15 = high -> read command
- * - raise CS and assert it again
- * - always clock in 16 clocks at once
- * - at DOUT: D15 first, D0 last
- * - D0..D7 contains the data from the first cycle
- *
- * The driver exports a standard gpiochip interface
+ * Check max730x.c for further details.
*/
+#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/spi/spi.h>
#include <linux/spi/max7301.h>
-#include <linux/gpio.h>
-
-#define DRIVER_NAME "max7301"
-
-/*
- * Pin configurations, see MAX7301 datasheet page 6
- */
-#define PIN_CONFIG_MASK 0x03
-#define PIN_CONFIG_IN_PULLUP 0x03
-#define PIN_CONFIG_IN_WO_PULLUP 0x02
-#define PIN_CONFIG_OUT 0x01
-
-#define PIN_NUMBER 28
-
-
-/*
- * Some registers must be read back to modify.
- * To save time we cache them here in memory
- */
-struct max7301 {
- struct mutex lock;
- u8 port_config[8]; /* field 0 is unused */
- u32 out_level; /* cached output levels */
- struct gpio_chip chip;
- struct spi_device *spi;
-};
-/**
- * max7301_write - Write a new register content
- * @spi: The SPI device
- * @reg: Register offset
- * @val: Value to write
- *
- * A write to the MAX7301 means one message with one transfer
- *
- * Returns 0 if successful or a negative value on error
- */
-static int max7301_write(struct spi_device *spi, unsigned int reg, unsigned int val)
+/* A write to the MAX7301 means one message with one transfer */
+static int max7301_spi_write(struct device *dev, unsigned int reg,
+ unsigned int val)
{
+ struct spi_device *spi = to_spi_device(dev);
u16 word = ((reg & 0x7F) << 8) | (val & 0xFF);
+
return spi_write(spi, (const u8 *)&word, sizeof(word));
}
-/**
- * max7301_read - Read back register content
- * @spi: The SPI device
- * @reg: Register offset
- *
- * A read from the MAX7301 means two transfers; here, one message each
- *
- * Returns positive 8 bit value from device if successful or a
- * negative value on error
- */
-static int max7301_read(struct spi_device *spi, unsigned int reg)
+/* A read from the MAX7301 means two transfers; here, one message each */
+
+static int max7301_spi_read(struct device *dev, unsigned int reg)
{
int ret;
u16 word;
+ struct spi_device *spi = to_spi_device(dev);
word = 0x8000 | (reg << 8);
ret = spi_write(spi, (const u8 *)&word, sizeof(word));
@@ -108,125 +51,13 @@ static int max7301_read(struct spi_devic
return word & 0xff;
}
-static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
-{
- struct max7301 *ts = container_of(chip, struct max7301, chip);
- u8 *config;
- int ret;
-
- /* First 4 pins are unused in the controller */
- offset += 4;
-
- config = &ts->port_config[offset >> 2];
-
- mutex_lock(&ts->lock);
-
- /* Standard GPIO API doesn't support pull-ups, has to be extended.
- * Hard-coding no pollup for now. */
- *config = (*config & ~(3 << (offset & 3))) | (1 << (offset & 3));
-
- ret = max7301_write(ts->spi, 0x08 + (offset >> 2), *config);
-
- mutex_unlock(&ts->lock);
-
- return ret;
-}
-
-static int __max7301_set(struct max7301 *ts, unsigned offset, int value)
-{
- if (value) {
- ts->out_level |= 1 << offset;
- return max7301_write(ts->spi, 0x20 + offset, 0x01);
- } else {
- ts->out_level &= ~(1 << offset);
- return max7301_write(ts->spi, 0x20 + offset, 0x00);
- }
-}
-
-static int max7301_direction_output(struct gpio_chip *chip, unsigned offset,
- int value)
-{
- struct max7301 *ts = container_of(chip, struct max7301, chip);
- u8 *config;
- int ret;
-
- /* First 4 pins are unused in the controller */
- offset += 4;
-
- config = &ts->port_config[offset >> 2];
-
- mutex_lock(&ts->lock);
-
- *config = (*config & ~(3 << (offset & 3))) | (1 << (offset & 3));
-
- ret = __max7301_set(ts, offset, value);
-
- if (!ret)
- ret = max7301_write(ts->spi, 0x08 + (offset >> 2), *config);
-
- mutex_unlock(&ts->lock);
-
- return ret;
-}
-
-static int max7301_get(struct gpio_chip *chip, unsigned offset)
-{
- struct max7301 *ts = container_of(chip, struct max7301, chip);
- int config, level = -EINVAL;
-
- /* First 4 pins are unused in the controller */
- offset += 4;
-
- mutex_lock(&ts->lock);
-
- config = (ts->port_config[offset >> 2] >> ((offset & 3) * 2)) & 3;
-
- switch (config) {
- case 1:
- /* Output: return cached level */
- level = !!(ts->out_level & (1 << offset));
- break;
- case 2:
- case 3:
- /* Input: read out */
- level = max7301_read(ts->spi, 0x20 + offset) & 0x01;
- }
- mutex_unlock(&ts->lock);
-
- return level;
-}
-
-static void max7301_set(struct gpio_chip *chip, unsigned offset, int value)
-{
- struct max7301 *ts = container_of(chip, struct max7301, chip);
-
- /* First 4 pins are unused in the controller */
- offset += 4;
-
- mutex_lock(&ts->lock);
-
- __max7301_set(ts, offset, value);
-
- mutex_unlock(&ts->lock);
-}
-
static int __devinit max7301_probe(struct spi_device *spi)
{
struct max7301 *ts;
- struct max7301_platform_data *pdata;
- int i, ret;
-
- pdata = spi->dev.platform_data;
- if (!pdata || !pdata->base) {
- dev_dbg(&spi->dev, "incorrect or missing platform data\n");
- return -EINVAL;
- }
+ int ret;
- /*
- * bits_per_word cannot be configured in platform data
- */
+ /* bits_per_word cannot be configured in platform data */
spi->bits_per_word = 16;
-
ret = spi_setup(spi);
if (ret < 0)
return ret;
@@ -235,90 +66,35 @@ static int __devinit max7301_probe(struc
if (!ts)
return -ENOMEM;
- mutex_init(&ts->lock);
-
- dev_set_drvdata(&spi->dev, ts);
-
- /* Power up the chip and disable IRQ output */
- max7301_write(spi, 0x04, 0x01);
-
- ts->spi = spi;
-
- ts->chip.label = DRIVER_NAME,
-
- ts->chip.direction_input = max7301_direction_input;
- ts->chip.get = max7301_get;
- ts->chip.direction_output = max7301_direction_output;
- ts->chip.set = max7301_set;
+ ts->read = max7301_spi_read;
+ ts->write = max7301_spi_write;
+ ts->dev = &spi->dev;
- ts->chip.base = pdata->base;
- ts->chip.ngpio = PIN_NUMBER;
- ts->chip.can_sleep = 1;
- ts->chip.dev = &spi->dev;
- ts->chip.owner = THIS_MODULE;
-
- /*
- * tristate all pins in hardware and cache the
- * register values for later use.
- */
- for (i = 1; i < 8; i++) {
- int j;
- /* 0xAA means input with internal pullup disabled */
- max7301_write(spi, 0x08 + i, 0xAA);
- ts->port_config[i] = 0xAA;
- for (j = 0; j < 4; j++) {
- int offset = (i - 1) * 4 + j;
- ret = max7301_direction_input(&ts->chip, offset);
- if (ret)
- goto exit_destroy;
- }
- }
-
- ret = gpiochip_add(&ts->chip);
+ ret = __max730x_probe(ts);
if (ret)
- goto exit_destroy;
-
- return ret;
-
-exit_destroy:
- dev_set_drvdata(&spi->dev, NULL);
- mutex_destroy(&ts->lock);
- kfree(ts);
+ kfree(ts);
return ret;
}
static int __devexit max7301_remove(struct spi_device *spi)
{
- struct max7301 *ts;
- int ret;
-
- ts = dev_get_drvdata(&spi->dev);
- if (ts == NULL)
- return -ENODEV;
-
- dev_set_drvdata(&spi->dev, NULL);
-
- /* Power down the chip and disable IRQ output */
- max7301_write(spi, 0x04, 0x00);
-
- ret = gpiochip_remove(&ts->chip);
- if (!ret) {
- mutex_destroy(&ts->lock);
- kfree(ts);
- } else
- dev_err(&spi->dev, "Failed to remove the GPIO controller: %d\n",
- ret);
-
- return ret;
+ return __max730x_remove(&spi->dev);
}
+static const struct spi_device_id max7301_id[] = {
+ { "max7301", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, max7301_id);
+
static struct spi_driver max7301_driver = {
.driver = {
- .name = DRIVER_NAME,
- .owner = THIS_MODULE,
+ .name = "max7301",
+ .owner = THIS_MODULE,
},
- .probe = max7301_probe,
- .remove = __devexit_p(max7301_remove),
+ .probe = max7301_probe,
+ .remove = __devexit_p(max7301_remove),
+ .id_table = max7301_id,
};
static int __init max7301_init(void)
@@ -336,7 +112,6 @@ static void __exit max7301_exit(void)
}
module_exit(max7301_exit);
-MODULE_AUTHOR("Juergen Beisert");
+MODULE_AUTHOR("Juergen Beisert, Wolfram Sang");
MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("MAX7301 SPI based GPIO-Expander");
-MODULE_ALIAS("spi:" DRIVER_NAME);
+MODULE_DESCRIPTION("MAX7301 GPIO-Expander");
diff -puN /dev/null drivers/gpio/max730x.c
--- /dev/null
+++ a/drivers/gpio/max730x.c
@@ -0,0 +1,244 @@
+/**
+ * drivers/gpio/max7301.c
+ *
+ * Copyright (C) 2006 Juergen Beisert, Pengutronix
+ * Copyright (C) 2008 Guennadi Liakhovetski, Pengutronix
+ * Copyright (C) 2009 Wolfram Sang, Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * The Maxim MAX7300/1 device is an I2C/SPI driven GPIO expander. There are
+ * 28 GPIOs. 8 of them can trigger an interrupt. See datasheet for more
+ * details
+ * Note:
+ * - DIN must be stable at the rising edge of clock.
+ * - when writing:
+ * - always clock in 16 clocks at once
+ * - at DIN: D15 first, D0 last
+ * - D0..D7 = databyte, D8..D14 = commandbyte
+ * - D15 = low -> write command
+ * - when reading
+ * - always clock in 16 clocks at once
+ * - at DIN: D15 first, D0 last
+ * - D0..D7 = dummy, D8..D14 = register address
+ * - D15 = high -> read command
+ * - raise CS and assert it again
+ * - always clock in 16 clocks at once
+ * - at DOUT: D15 first, D0 last
+ * - D0..D7 contains the data from the first cycle
+ *
+ * The driver exports a standard gpiochip interface
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/spi/max7301.h>
+#include <linux/gpio.h>
+
+/*
+ * Pin configurations, see MAX7301 datasheet page 6
+ */
+#define PIN_CONFIG_MASK 0x03
+#define PIN_CONFIG_IN_PULLUP 0x03
+#define PIN_CONFIG_IN_WO_PULLUP 0x02
+#define PIN_CONFIG_OUT 0x01
+
+#define PIN_NUMBER 28
+
+static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ struct max7301 *ts = container_of(chip, struct max7301, chip);
+ u8 *config;
+ u8 offset_bits;
+ int ret;
+
+ /* First 4 pins are unused in the controller */
+ offset += 4;
+ offset_bits = (offset & 3) << 1;
+
+ config = &ts->port_config[offset >> 2];
+
+ mutex_lock(&ts->lock);
+
+ /* Standard GPIO API doesn't support pull-ups, has to be extended.
+ * Hard-coding no pollup for now. */
+ *config = (*config & ~(PIN_CONFIG_MASK << offset_bits))
+ | (PIN_CONFIG_IN_WO_PULLUP << offset_bits);
+
+ ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);
+
+ mutex_unlock(&ts->lock);
+
+ return ret;
+}
+
+static int __max7301_set(struct max7301 *ts, unsigned offset, int value)
+{
+ if (value) {
+ ts->out_level |= 1 << offset;
+ return ts->write(ts->dev, 0x20 + offset, 0x01);
+ } else {
+ ts->out_level &= ~(1 << offset);
+ return ts->write(ts->dev, 0x20 + offset, 0x00);
+ }
+}
+
+static int max7301_direction_output(struct gpio_chip *chip, unsigned offset,
+ int value)
+{
+ struct max7301 *ts = container_of(chip, struct max7301, chip);
+ u8 *config;
+ u8 offset_bits;
+ int ret;
+
+ /* First 4 pins are unused in the controller */
+ offset += 4;
+ offset_bits = (offset & 3) << 1;
+
+ config = &ts->port_config[offset >> 2];
+
+ mutex_lock(&ts->lock);
+
+ *config = (*config & ~(PIN_CONFIG_MASK << offset_bits))
+ | (PIN_CONFIG_OUT << offset_bits);
+
+ ret = __max7301_set(ts, offset, value);
+
+ if (!ret)
+ ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);
+
+ mutex_unlock(&ts->lock);
+
+ return ret;
+}
+
+static int max7301_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct max7301 *ts = container_of(chip, struct max7301, chip);
+ int config, level = -EINVAL;
+
+ /* First 4 pins are unused in the controller */
+ offset += 4;
+
+ mutex_lock(&ts->lock);
+
+ config = (ts->port_config[offset >> 2] >> ((offset & 3) << 1))
+ & PIN_CONFIG_MASK;
+
+ switch (config) {
+ case PIN_CONFIG_OUT:
+ /* Output: return cached level */
+ level = !!(ts->out_level & (1 << offset));
+ break;
+ case PIN_CONFIG_IN_WO_PULLUP:
+ case PIN_CONFIG_IN_PULLUP:
+ /* Input: read out */
+ level = ts->read(ts->dev, 0x20 + offset) & 0x01;
+ }
+ mutex_unlock(&ts->lock);
+
+ return level;
+}
+
+static void max7301_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct max7301 *ts = container_of(chip, struct max7301, chip);
+
+ /* First 4 pins are unused in the controller */
+ offset += 4;
+
+ mutex_lock(&ts->lock);
+
+ __max7301_set(ts, offset, value);
+
+ mutex_unlock(&ts->lock);
+}
+
+int __devinit __max730x_probe(struct max7301 *ts)
+{
+ struct device *dev = ts->dev;
+ struct max7301_platform_data *pdata;
+ int i, ret;
+
+ pdata = dev->platform_data;
+ if (!pdata || !pdata->base) {
+ dev_err(dev, "incorrect or missing platform data\n");
+ return -EINVAL;
+ }
+
+ mutex_init(&ts->lock);
+ dev_set_drvdata(dev, ts);
+
+ /* Power up the chip and disable IRQ output */
+ ts->write(dev, 0x04, 0x01);
+
+ ts->chip.label = dev->driver->name;
+
+ ts->chip.direction_input = max7301_direction_input;
+ ts->chip.get = max7301_get;
+ ts->chip.direction_output = max7301_direction_output;
+ ts->chip.set = max7301_set;
+
+ ts->chip.base = pdata->base;
+ ts->chip.ngpio = PIN_NUMBER;
+ ts->chip.can_sleep = 1;
+ ts->chip.dev = dev;
+ ts->chip.owner = THIS_MODULE;
+
+ /*
+ * tristate all pins in hardware and cache the
+ * register values for later use.
+ */
+ for (i = 1; i < 8; i++) {
+ int j;
+ /* 0xAA means input with internal pullup disabled */
+ ts->write(dev, 0x08 + i, 0xAA);
+ ts->port_config[i] = 0xAA;
+ for (j = 0; j < 4; j++) {
+ int offset = (i - 1) * 4 + j;
+ ret = max7301_direction_input(&ts->chip, offset);
+ if (ret)
+ goto exit_destroy;
+ }
+ }
+
+ ret = gpiochip_add(&ts->chip);
+ if (ret)
+ goto exit_destroy;
+
+ return ret;
+
+exit_destroy:
+ dev_set_drvdata(dev, NULL);
+ mutex_destroy(&ts->lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__max730x_probe);
+
+int __devexit __max730x_remove(struct device *dev)
+{
+ struct max7301 *ts = dev_get_drvdata(dev);
+ int ret;
+
+ if (ts == NULL)
+ return -ENODEV;
+
+ dev_set_drvdata(dev, NULL);
+
+ /* Power down the chip and disable IRQ output */
+ ts->write(dev, 0x04, 0x00);
+
+ ret = gpiochip_remove(&ts->chip);
+ if (!ret) {
+ mutex_destroy(&ts->lock);
+ kfree(ts);
+ } else
+ dev_err(dev, "Failed to remove GPIO controller: %d\n", ret);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__max730x_remove);
diff -puN include/linux/spi/max7301.h~gpio-add-driver-for-max7300-i2c-gpio-extender include/linux/spi/max7301.h
--- a/include/linux/spi/max7301.h~gpio-add-driver-for-max7300-i2c-gpio-extender
+++ a/include/linux/spi/max7301.h
@@ -1,9 +1,27 @@
#ifndef LINUX_SPI_MAX7301_H
#define LINUX_SPI_MAX7301_H
+#include <linux/gpio.h>
+
+/*
+ * Some registers must be read back to modify.
+ * To save time we cache them here in memory
+ */
+struct max7301 {
+ struct mutex lock;
+ u8 port_config[8]; /* field 0 is unused */
+ u32 out_level; /* cached output levels */
+ struct gpio_chip chip;
+ struct device *dev;
+ int (*write)(struct device *dev, unsigned int reg, unsigned int val);
+ int (*read)(struct device *dev, unsigned int reg);
+};
+
struct max7301_platform_data {
/* number assigned to the first GPIO */
unsigned base;
};
+extern int __max730x_remove(struct device *dev);
+extern int __max730x_probe(struct max7301 *ts);
#endif
_
Patches currently in -mm which might be from w.sang@pengutronix.de are
origin.patch
linux-next.patch
checkpatch-fix-false-positive-on-__initconst.patch
gpio-add-driver-for-max7300-i2c-gpio-extender.patch
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2009-12-16 21:57 UTC | newest]
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2009-11-20 23:34 + gpio-add-driver-for-max7300-i2c-gpio-extender.patch added to -mm tree akpm
2009-12-16 21:57 akpm
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