* [PATCH 2/4] add stih-cec driver
2016-09-14 9:22 [PATCH 0/4] STIH CEC driver Benjamin Gaignard
2016-09-14 9:22 ` [PATCH 1/4] bindings for stih-cec driver Benjamin Gaignard
@ 2016-09-14 9:22 ` Benjamin Gaignard
2016-09-14 9:22 ` [PATCH 3/4] add stih-cec driver into DT Benjamin Gaignard
2016-09-14 9:22 ` [PATCH 4/4] add maintainer for stih-cec driver Benjamin Gaignard
3 siblings, 0 replies; 6+ messages in thread
From: Benjamin Gaignard @ 2016-09-14 9:22 UTC (permalink / raw)
To: hans.verkuil, linux-media; +Cc: kernel, arnd, robh, Benjamin Gaignard
This patch implement CEC driver for stih4xx platform.
Driver compliance has been test with cec-ctl and
cec-compliance tools.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
---
drivers/staging/media/Kconfig | 2 +
drivers/staging/media/Makefile | 1 +
drivers/staging/media/st-cec/Kconfig | 8 +
drivers/staging/media/st-cec/Makefile | 1 +
drivers/staging/media/st-cec/stih-cec.c | 377 ++++++++++++++++++++++++++++++++
5 files changed, 389 insertions(+)
create mode 100644 drivers/staging/media/st-cec/Kconfig
create mode 100644 drivers/staging/media/st-cec/Makefile
create mode 100644 drivers/staging/media/st-cec/stih-cec.c
diff --git a/drivers/staging/media/Kconfig b/drivers/staging/media/Kconfig
index 7292f23..699719b 100644
--- a/drivers/staging/media/Kconfig
+++ b/drivers/staging/media/Kconfig
@@ -38,4 +38,6 @@ source "drivers/staging/media/s5p-cec/Kconfig"
# Keep LIRC at the end, as it has sub-menus
source "drivers/staging/media/lirc/Kconfig"
+source "drivers/staging/media/st-cec/Kconfig"
+
endif
diff --git a/drivers/staging/media/Makefile b/drivers/staging/media/Makefile
index 87ce8ad..03cf58c 100644
--- a/drivers/staging/media/Makefile
+++ b/drivers/staging/media/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_VIDEO_DM365_VPFE) += davinci_vpfe/
obj-$(CONFIG_VIDEO_OMAP4) += omap4iss/
obj-$(CONFIG_USB_PULSE8_CEC) += pulse8-cec/
obj-$(CONFIG_VIDEO_TW686X_KH) += tw686x-kh/
+obj-$(CONFIG_VIDEO_STIH_CEC) += st-cec/
diff --git a/drivers/staging/media/st-cec/Kconfig b/drivers/staging/media/st-cec/Kconfig
new file mode 100644
index 0000000..c9a8328
--- /dev/null
+++ b/drivers/staging/media/st-cec/Kconfig
@@ -0,0 +1,8 @@
+config VIDEO_STIH_CEC
+ tristate "STIH4xx CEC driver"
+ depends on VIDEO_DEV && MEDIA_CEC && (ARCH_STI || COMPILE_TEST)
+ ---help---
+ This is a driver for STIH4xx HDMI CEC interface. It uses the
+ generic CEC framework interface.
+ CEC bus is present in the HDMI connector and enables communication
+ between compatible devices.
diff --git a/drivers/staging/media/st-cec/Makefile b/drivers/staging/media/st-cec/Makefile
new file mode 100644
index 0000000..375ea24
--- /dev/null
+++ b/drivers/staging/media/st-cec/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_VIDEO_STIH_CEC) += stih-cec.o
diff --git a/drivers/staging/media/st-cec/stih-cec.c b/drivers/staging/media/st-cec/stih-cec.c
new file mode 100644
index 0000000..09692e3
--- /dev/null
+++ b/drivers/staging/media/st-cec/stih-cec.c
@@ -0,0 +1,377 @@
+/*
+ * drivers/staging/media/st-cec/stih-cec.c
+ *
+ * STIH4xx CEC driver
+ * Copyright (C) STMicroelectronic SA 2016
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/version.h>
+#include <media/cec.h>
+
+#define CEC_NAME "stih-cec"
+
+/* CEC registers */
+#define CEC_CLK_DIV 0x0
+#define CEC_CTRL 0x4
+#define CEC_IRQ_CTRL 0x8
+#define CEC_STATUS 0xC
+#define CEC_EXT_STATUS 0x10
+#define CEC_TX_CTRL 0x14
+#define CEC_FREE_TIME_THRESH 0x18
+#define CEC_BIT_TOUT_THRESH 0x1C
+#define CEC_BIT_PULSE_THRESH 0x20
+#define CEC_DATA 0x24
+#define CEC_TX_ARRAY_CTRL 0x28
+#define CEC_CTRL2 0x2C
+#define CEC_TX_ERROR_STS 0x30
+#define CEC_ADDR_TABLE 0x34
+#define CEC_DATA_ARRAY_CTRL 0x38
+#define CEC_DATA_ARRAY_STATUS 0x3C
+#define CEC_TX_DATA_BASE 0x40
+#define CEC_TX_DATA_TOP 0x50
+#define CEC_TX_DATA_SIZE 0x1
+#define CEC_RX_DATA_BASE 0x54
+#define CEC_RX_DATA_TOP 0x64
+#define CEC_RX_DATA_SIZE 0x1
+
+/* CEC_CTRL2*/
+#define CEC_LINE_INACTIVE_EN BIT(0)
+#define CEC_AUTO_BUS_ERR_EN BIT(1)
+#define CEC_STOP_ON_ARB_ERR_EN BIT(2)
+#define CEC_TX_REQ_WAIT_EN BIT(3)
+
+/* CEC_DATA_ARRAY_CTRL*/
+#define CEC_TX_ARRAY_EN BIT(0)
+#define CEC_RX_ARRAY_EN BIT(1)
+#define CEC_TX_ARRAY_RESET BIT(2)
+#define CEC_RX_ARRAY_RESET BIT(3)
+#define CEC_TX_N_OF_BYTES_IRQ_EN BIT(4)
+#define CEC_TX_STOP_ON_NACK BIT(7)
+
+/* CEC_TX_ARRAY_CTRL*/
+#define CEC_TX_N_OF_BYTES 0x1F
+#define CEC_TX_START BIT(5)
+#define CEC_TX_AUTO_SOM_EN BIT(6)
+#define CEC_TX_AUTO_EOM_EN BIT(7)
+
+/* CEC_IRQ_CTRL*/
+#define CEC_TX_DONE_IRQ_EN BIT(0)
+#define CEC_ERROR_IRQ_EN BIT(2)
+#define CEC_RX_DONE_IRQ_EN BIT(3)
+#define CEC_RX_SOM_IRQ_EN BIT(4)
+#define CEC_RX_EOM_IRQ_EN BIT(5)
+#define CEC_FREE_TIME_IRQ_EN BIT(6)
+#define CEC_PIN_STS_IRQ_EN BIT(7)
+
+/* CEC_CTRL*/
+#define CEC_IN_FILTER_EN BIT(0)
+#define CEC_PWR_SAVE_EN BIT(1)
+#define CEC_EN BIT(4)
+#define CEC_ACK_CTRL BIT(5)
+#define CEC_RX_RESET_EN BIT(6)
+#define CEC_IGNORE_RX_ERROR BIT(7)
+
+/* CEC_STATUS*/
+#define CEC_TX_DONE_STS BIT(0)
+#define CEC_TX_ACK_GET_STS BIT(1)
+#define CEC_ERROR_STS BIT(2)
+#define CEC_RX_DONE_STS BIT(3)
+#define CEC_RX_SOM_STS BIT(4)
+#define CEC_RX_EOM_STS BIT(5)
+#define CEC_FREE_TIME_IRQ_STS BIT(6)
+#define CEC_PIN_STS BIT(7)
+#define CEC_SBIT_TOUT_STS BIT(8)
+#define CEC_DBIT_TOUT_STS BIT(9)
+#define CEC_LPULSE_ERROR_STS BIT(10)
+#define CEC_HPULSE_ERROR_STS BIT(11)
+#define CEC_TX_ERROR BIT(12)
+#define CEC_TX_ARB_ERROR BIT(13)
+#define CEC_RX_ERROR_MIN BIT(14)
+#define CEC_RX_ERROR_MAX BIT(15)
+
+/* Signal free time in bit periods (2.4ms)*/
+#define CEC_PRESENT_INIT_SFT 7
+#define CEC_NEW_INIT_SFT 5
+#define CEC_RETRANSMIT_SFT 3
+
+/* Constants for CEC_BIT_TOUT_THRESH register */
+#define CEC_SBIT_TOUT_47MS 0x02
+#define CEC_SBIT_TOUT_48MS 0x03
+#define CEC_SBIT_TOUT_50MS 0x04
+#define CEC_DBIT_TOUT_27MS 0x01
+#define CEC_DBIT_TOUT_28MS 0x02
+#define CEC_DBIT_TOUT_29MS 0x03
+
+/* Constants for CEC_BIT_PULSE_THRESH register */
+#define CEC_BIT_LPULSE_03MS 0x02
+#define CEC_BIT_HPULSE_03MS 0x08
+
+/* Constants for CEC_DATA_ARRAY_STATUS register*/
+#define CEC_RX_N_OF_BYTES 0x1F
+#define CEC_TX_N_OF_BYTES_SENT BIT(5)
+#define CEC_RX_OVERRUN BIT(6)
+
+struct stih_cec {
+ struct cec_adapter *adap;
+ struct device *dev;
+ struct clk *clk;
+ void __iomem *regs;
+ int irq;
+ u32 irq_status;
+ struct cec_msg rx_msg;
+};
+
+static int stih_cec_adap_enable(struct cec_adapter *adap, bool enable)
+{
+ struct stih_cec *cec = adap->priv;
+
+ if (enable) {
+ /* The doc says (input TCLK_PERIOD * CEC_CLK_DIV) = 0.1ms */
+ unsigned long clk_freq = clk_get_rate(cec->clk);
+ u32 cec_clk_div = clk_freq / 10000;
+
+ writel(cec_clk_div, cec->regs + CEC_CLK_DIV);
+
+ /*Configuration of the durations activating a timeout*/
+ writel(CEC_SBIT_TOUT_47MS | (CEC_DBIT_TOUT_28MS << 4),
+ cec->regs + CEC_BIT_TOUT_THRESH);
+
+ /*Configuration of the smallest allowed duration for pulses*/
+ writel(CEC_BIT_LPULSE_03MS | CEC_BIT_HPULSE_03MS,
+ cec->regs + CEC_BIT_PULSE_THRESH);
+
+ /*Minimum received bit period threshold*/
+ writel(BIT(5) | BIT(7), cec->regs + CEC_TX_CTRL);
+
+ /*Configuration of transceiver data arrays */
+ writel(CEC_TX_ARRAY_EN | CEC_RX_ARRAY_EN | CEC_TX_STOP_ON_NACK,
+ cec->regs + CEC_DATA_ARRAY_CTRL);
+
+ /*Configuration of the control bits for CEC Transceiver*/
+ writel(CEC_IN_FILTER_EN | CEC_EN | CEC_RX_RESET_EN,
+ cec->regs + CEC_CTRL);
+
+ /* clear logical addresses */
+ writel(0, cec->regs + CEC_ADDR_TABLE);
+
+ /*Clear the status register*/
+ writel(0x0, cec->regs + CEC_STATUS);
+
+ /*Enable the interrupts*/
+ writel(CEC_TX_DONE_IRQ_EN | CEC_RX_DONE_IRQ_EN |
+ CEC_RX_SOM_IRQ_EN | CEC_RX_EOM_IRQ_EN |
+ CEC_ERROR_IRQ_EN,
+ cec->regs + CEC_IRQ_CTRL);
+
+ } else {
+ /* clear logical addresses */
+ writel(0, cec->regs + CEC_ADDR_TABLE);
+
+ /*Clear the status register*/
+ writel(0x0, cec->regs + CEC_STATUS);
+
+ /*Disable the interrupts*/
+ writel(0, cec->regs + CEC_IRQ_CTRL);
+ }
+
+ return 0;
+}
+
+static int stih_cec_adap_log_addr(struct cec_adapter *adap, u8 logical_addr)
+{
+ struct stih_cec *cec = adap->priv;
+ u32 reg = readl(cec->regs + CEC_ADDR_TABLE);
+
+ if (logical_addr == CEC_LOG_ADDR_INVALID)
+ reg = 0;
+ else
+ reg |= 1 << logical_addr;
+
+ writel(reg, cec->regs + CEC_ADDR_TABLE);
+ return 0;
+}
+
+static int stih_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
+ u32 signal_free_time, struct cec_msg *msg)
+{
+ struct stih_cec *cec = adap->priv;
+ int i;
+
+ /* Copy message into registers */
+ for (i = 0; i < msg->len; i++)
+ writeb(msg->msg[i], cec->regs + CEC_TX_DATA_BASE + i);
+
+ /* start transmission */
+ writel(CEC_TX_AUTO_SOM_EN | CEC_TX_AUTO_EOM_EN | CEC_TX_START |
+ msg->len, cec->regs + CEC_TX_ARRAY_CTRL);
+
+ return 0;
+}
+
+static void stih_tx_done(struct stih_cec *cec, u32 status)
+{
+ if (status & CEC_TX_ERROR) {
+ cec_transmit_done(cec->adap, CEC_TX_STATUS_ERROR, 0, 0, 0, 1);
+ return;
+ }
+
+ if (status & CEC_TX_ARB_ERROR) {
+ cec_transmit_done(cec->adap,
+ CEC_TX_STATUS_ARB_LOST, 1, 0, 0, 0);
+ return;
+ }
+
+ if (!(status & CEC_TX_ACK_GET_STS)) {
+ cec_transmit_done(cec->adap, CEC_TX_STATUS_NACK, 0, 1, 0, 0);
+ return;
+ }
+
+ cec_transmit_done(cec->adap, CEC_TX_STATUS_OK, 0, 0, 0, 0);
+}
+
+static void stih_rx_done(struct stih_cec *cec, u32 status)
+{
+ struct cec_msg *msg = &cec->rx_msg;
+
+ if (status & CEC_RX_ERROR_MIN)
+ return;
+
+ if (status & CEC_RX_ERROR_MAX)
+ return;
+
+ memset(msg, 0x00, sizeof(*msg));
+ msg->len = readl(cec->regs + CEC_DATA_ARRAY_STATUS) & 0x1f;
+
+ if (msg->len > 16)
+ msg->len = 16;
+
+ if (msg->len) {
+ u8 i;
+
+ for (i = 0; i < msg->len; i++)
+ msg->msg[i] = readl(cec->regs + CEC_RX_DATA_BASE + i);
+
+ cec_received_msg(cec->adap, msg);
+ }
+}
+
+static irqreturn_t stih_cec_irq_handler_thread(int irq, void *priv)
+{
+ struct stih_cec *cec = priv;
+
+ if (cec->irq_status & CEC_TX_DONE_STS)
+ stih_tx_done(cec, cec->irq_status);
+
+ if (cec->irq_status & CEC_RX_DONE_STS)
+ stih_rx_done(cec, cec->irq_status);
+
+ cec->irq_status = 0;
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t stih_cec_irq_handler(int irq, void *priv)
+{
+ struct stih_cec *cec = priv;
+
+ cec->irq_status = readl(cec->regs + CEC_STATUS);
+ writel(cec->irq_status, cec->regs + CEC_STATUS);
+
+ return IRQ_WAKE_THREAD;
+}
+
+static const struct cec_adap_ops sti_cec_adap_ops = {
+ .adap_enable = stih_cec_adap_enable,
+ .adap_log_addr = stih_cec_adap_log_addr,
+ .adap_transmit = stih_cec_adap_transmit,
+};
+
+static int stih_cec_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ struct stih_cec *cec;
+ int ret;
+
+ cec = devm_kzalloc(dev, sizeof(*cec), GFP_KERNEL);
+ if (!cec)
+ return -ENOMEM;
+
+ cec->dev = dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ cec->regs = devm_ioremap_resource(dev, res);
+ if (IS_ERR(cec->regs))
+ return PTR_ERR(cec->regs);
+
+ cec->irq = platform_get_irq(pdev, 0);
+ if (cec->irq < 0)
+ return cec->irq;
+
+ ret = devm_request_threaded_irq(dev, cec->irq, stih_cec_irq_handler,
+ stih_cec_irq_handler_thread, 0,
+ pdev->name, cec);
+ if (ret)
+ return ret;
+
+ cec->clk = devm_clk_get(dev, "cec-clk");
+ if (IS_ERR(cec->clk)) {
+ dev_err(dev, "Cannot get cec clock\n");
+ return PTR_ERR(cec->clk);
+ }
+
+ cec->adap = cec_allocate_adapter(&sti_cec_adap_ops, cec,
+ CEC_NAME,
+ CEC_CAP_LOG_ADDRS | CEC_CAP_PASSTHROUGH |
+ CEC_CAP_PHYS_ADDR | CEC_CAP_TRANSMIT,
+ 1, &pdev->dev);
+ ret = PTR_ERR_OR_ZERO(cec->adap);
+ if (ret)
+ return ret;
+
+ ret = cec_register_adapter(cec->adap);
+ if (ret) {
+ cec_delete_adapter(cec->adap);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, cec);
+ return 0;
+}
+
+static int stih_cec_remove(struct platform_device *pdev)
+{
+ return 0;
+}
+
+static const struct of_device_id stih_cec_match[] = {
+ {
+ .compatible = "st,stih-cec",
+ },
+ {},
+};
+
+static struct platform_driver stih_cec_pdrv = {
+ .probe = stih_cec_probe,
+ .remove = stih_cec_remove,
+ .driver = {
+ .name = CEC_NAME,
+ .of_match_table = stih_cec_match,
+ },
+};
+
+module_platform_driver(stih_cec_pdrv);
+
+MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@linaro.org>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("STIH4xx CEC driver");
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread