Re: [Patch v1 08/11] Touch: DA9052 touchscreen driver

Hi Ashish,

On Thu, Jul 14, 2011 at 02:28:10PM +0530, ashishj3 wrote:

This driver add support for DA9052 4-wire resistive ADC interfaced touchscreen controller.

DA9052 is a MFD therefore this driver depends on DA9052 core driver for core functionalities.

Signed-off-by: David Dajun Chen dchen@diasemi.com Signed-off-by: Ashish Jangam ashish.jangam@kpitcummins.com

---

drivers/input/touchscreen/Kconfig | 7 + drivers/input/touchscreen/Makefile | 1 + drivers/input/touchscreen/da9052_tsi.c | 489 ++++++++++++++++++++++++++++++++ 3 files changed, 497 insertions(+), 0 deletions(-) create mode 100755 drivers/input/touchscreen/da9052_tsi.c diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig index cabd9e5..a5d2e7b 100644 --- a/drivers/input/touchscreen/Kconfig +++ b/drivers/input/touchscreen/Kconfig @@ -144,6 +144,13 @@ config TOUCHSCREEN_DA9034 Say Y here to enable the support for the touchscreen found on Dialog Semiconductor DA9034 PMIC. +config TOUCHSCREEN_DA9052

• tristate "Dialog DA9052 TSI"
• depends on PMIC_DA9052
• help

•  Say y here to support the touchscreen found on
  

•  Dialog Semiconductor DA9052 PMIC
  

To compile this driver as a module...

config TOUCHSCREEN_DYNAPRO tristate "Dynapro serial touchscreen" select SERIO diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile index 282d6f7..a4aeb25 100644 --- a/drivers/input/touchscreen/Makefile +++ b/drivers/input/touchscreen/Makefile @@ -18,6 +18,7 @@ obj-$(CONFIG_TOUCHSCREEN_BITSY) += h3600_ts_input.o obj-$(CONFIG_TOUCHSCREEN_BU21013) += bu21013_ts.o obj-$(CONFIG_TOUCHSCREEN_CY8CTMG110) += cy8ctmg110_ts.o obj-$(CONFIG_TOUCHSCREEN_DA9034) += da9034-ts.o +obj-$(CONFIG_TOUCHSCREEN_DA9052) += da9052_tsi.o obj-$(CONFIG_TOUCHSCREEN_DYNAPRO) += dynapro.o obj-$(CONFIG_TOUCHSCREEN_HAMPSHIRE) += hampshire.o obj-$(CONFIG_TOUCHSCREEN_GUNZE) += gunze.o diff --git a/drivers/input/touchscreen/da9052_tsi.c b/drivers/input/touchscreen/da9052_tsi.c new file mode 100755 index 0000000..dade0a9 --- /dev/null +++ b/drivers/input/touchscreen/da9052_tsi.c @@ -0,0 +1,489 @@ +/*

• • TSI driver for Dialog DA9052
• • Copyright(c) 2011 Dialog Semiconductor Ltd.
• • Author: David Dajun Chen dchen@diasemi.com
• • 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/module.h> +#include <linux/input.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/freezer.h> +#include <linux/kthread.h> +#include <linux/kfifo.h>

+#include <linux/mfd/da9052/reg.h> +#include <linux/mfd/da9052/da9052.h>

+#define DA9052_ACTIVE 1 +#define DA9052_INACTIVE 0

+#define DA9052_TSI_FIFOSIZE 640

+enum {

• DA9052_PEN_IDLE,
• DA9052_PEN_DOWN,
• DA9052_PEN_UP

+};

+struct da9052_tsi_reg {

• u16 x;
• u16 y;

+};

+struct tsi_thread_type {

• u8 pid;
• u8 state;
• struct completion notifier;
• struct task_struct *thread_task;

+};

What is the reason for rolling out your own kernel thread implementation? From what I understand you just need periodically to check for "pen up" and that's it, so simply use standard workqueue to schedule checks.

+struct da9052_tsi {

• struct da9052 *da9052;
• struct input_dev *dev;
• struct tsi_thread_type tsi_pen_state_thread;
• struct tsi_thread_type tsi_filter_thread;
• struct kfifo fifo;
• struct kfifo fifo_buf;
• u8 pen_up_detect_interval;
• u32 zero_data_cnt;
• u32 valid_penup_count;
• u8 pen_state;
• int irq_pendwn;
• int irq_datardy;

+};

+static inline int da9052_ts_start(struct da9052_tsi *tsi)

Drop inline, let compiler figure out if the function needs to be inlined.

Normally only fucntions in header files should be marked as static inline.

+{

• return da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG,

• 		 1 << 0, 1 << 0);
  

+}

+static inline int da9052_ts_stop(struct da9052_tsi *tsi) +{

• return da9052_clear_bits(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 0);

+}

+static irqreturn_t da9052_ts_pendwn_irq(int irq, void *data) +{

• struct da9052_tsi *tsi = (struct da9052_tsi *)data;
• struct da9052 *da9052 = tsi->da9052;
• int ret;
• da9052->events_mask |= DA9052_E_PEN_DOWN;
• da9052->events_mask &= ~DA9052_E_TSI_READY;
• /* Mask PEN_DOWN event and unmask TSI_READY event*/
• ret = da9052_reg_update(da9052, DA9052_IRQ_MASK_B_REG, 0x80, 0x40);
• if (ret < 0)

• return IRQ_NONE;
  

• da9052_ts_start(tsi);
• tsi->pen_state = DA9052_PEN_DOWN;
• return IRQ_HANDLED;

+}

+static int da9052_ts_read(struct da9052_tsi *tsi) +{

• struct da9052_tsi_reg co_ord = {0, 0};
• int ret;
• uint8_t _x, _y, _v;
• ret = da9052_reg_read(tsi->da9052, DA9052_TSI_X_MSB_REG);
• if (ret < 0)

• return ret;
  

• _x = (uint8_t) ret;
• ret = da9052_reg_read(tsi->da9052, DA9052_TSI_Y_MSB_REG);
• if (ret < 0)

• return ret;
  

• _y = (uint8_t) ret;
• ret = da9052_reg_read(tsi->da9052, DA9052_TSI_LSB_REG);
• if (ret < 0)

• return ret;
  

• _v = (uint8_t) ret;
• co_ord.x = ((_x << 2) & 0x3fc) | (_v & 0x3);
• co_ord.y = ((_y << 2) & 0x3fc) | ((_v & 0xc) >> 2);
• ret = kfifo_in(&tsi->fifo, &co_ord, sizeof(struct da9052_tsi_reg));

You have data, you know the pen state, why mess with 2! kfifos? Just report the events right here.

• return 0;

+}

+static irqreturn_t da9052_ts_datardy_irq(int irq, void *data) +{

• struct da9052_tsi *tsi = (struct da9052_tsi *)data;
• int ret;
• ret = da9052_ts_read(tsi);
• if (ret) {

• dev_err(tsi->da9052->dev,
  

• 	"Failed to read TSI co-ordinate, %d\n", ret);
  

• return IRQ_NONE;
  

• }
• return IRQ_HANDLED;

+}

+/* +* Two FIFO are been used. FIFO1 is used for detecting pen up and +* FIFO2 for reporting pen down co-ordinate. +*/ +void da9052_ts_process_reg_data(struct da9052_tsi *tsi) +{

• struct da9052_tsi_reg tmp_raw_data;
• u32 reg_data_cnt;
• int ret;
• reg_data_cnt = kfifo_len(&tsi->fifo);
• while (reg_data_cnt-- > 0) {

• ret = kfifo_out(&tsi->fifo, &tmp_raw_data,
  

• 		sizeof(struct da9052_tsi_reg));
  

• if (ret < 0)
  

• 	continue;
  

• kfifo_in(&tsi->fifo_buf, &tmp_raw_data,
  

• 	 sizeof(struct da9052_tsi_reg));
  

• }
• return;

+}

+static void da9052_ts_report_penup(struct da9052_tsi *tsi) +{

• struct input_dev *ip_dev = tsi->dev;
• struct da9052 *da9052 = tsi->da9052;
• ssize_t ret;
• ret = da9052_ts_stop(tsi);
• if (ret < 0)

• return;
  

• da9052->events_mask |= DA9052_E_TSI_READY;
• da9052->events_mask &= ~DA9052_E_PEN_DOWN;
• /* Mask TSI_READY event and unmask PEN_DOWN event*/
• ret = da9052_reg_update(da9052, DA9052_IRQ_MASK_B_REG, 0x40, 0x80);
• if (ret < 0)

• return;
  

• input_report_abs(ip_dev, BTN_TOUCH, 0);
• input_sync(ip_dev);
• tsi->zero_data_cnt = 0;

+}

+/* +* This function detects the pen up state using the kfifo len. +* If kfifo len is zero for some interval then pen up is reported. +* Else pen co-ordinate are reported. +*/ +static int da9052_ts_monitor_pen_state(void *data) +{

• struct da9052_tsi *tsi = (struct da9052_tsi *) data;
• u32 data_cnt;
• set_freezable();
• while (tsi->tsi_pen_state_thread.state == DA9052_ACTIVE) {

• try_to_freeze();
  

• set_current_state(TASK_INTERRUPTIBLE);
  

• schedule_timeout(msecs_to_jiffies(10));
  

• if (tsi->pen_state != DA9052_PEN_DOWN)
  

• 	continue;
  

• data_cnt = kfifo_len(&tsi->fifo);
  

• if (data_cnt < 0)
  

• 	continue;
  

• da9052_ts_process_reg_data(tsi);
  

• if (data_cnt)
  

• 	tsi->zero_data_cnt = 0;
  

• else {
  

• 	if ((++(tsi->zero_data_cnt)) >
  

• 		tsi->valid_penup_count) {
  

• 		tsi->pen_state = DA9052_PEN_UP;
  

• 		da9052_ts_report_penup(tsi);
  

• 	}
  

• }
  

• }
• complete_and_exit(&tsi->tsi_pen_state_thread.notifier, 0);
• return 0;

+}

+static int da9052_ts_process_thread(void *ptr) +{

• struct da9052_tsi_reg co_ord;
• int cnt = 0, ret;
• struct da9052_tsi *tsi = (struct da9052_tsi *)ptr;
• set_freezable();
• while (tsi->tsi_filter_thread.state == DA9052_ACTIVE) {

• try_to_freeze();
  

• set_current_state(TASK_INTERRUPTIBLE);
  

• schedule_timeout(msecs_to_jiffies(10));
  

• cnt = kfifo_len(&tsi->fifo_buf);
  

• if (cnt <= 0)
  

• 	continue;
  

• ret = kfifo_out(&tsi->fifo_buf, &co_ord,
  

• 		sizeof(struct da9052_tsi_reg));
  

• if (ret < 0)
  

• 	continue;
  

• input_report_abs(tsi->dev, BTN_TOUCH, 1);
  

• input_report_abs(tsi->dev, ABS_X, co_ord.x);
  

• input_report_abs(tsi->dev, ABS_Y, co_ord.y);
  

• input_sync(tsi->dev);
  

• }
• tsi->tsi_filter_thread.thread_task = NULL;
• complete_and_exit(&tsi->tsi_filter_thread.notifier, 0);
• return 0;

+}

+static int da9052_ts_configure_gpio(struct da9052 *da9052) +{

• int ret;
• ret = da9052_clear_bits(da9052, DA9052_GPIO_2_3_REG, 0x30);
• if (ret < 0)

• return -EIO;
  

• ret = da9052_clear_bits(da9052, DA9052_GPIO_4_5_REG, 0x33);
• if (ret < 0)

• return -EIO;
  

• ret = da9052_clear_bits(da9052, DA9052_GPIO_6_7_REG, 0x33);
• if (ret < 0)

• return -EIO;
  

• return ret;

+}

+static int __init da9052_ts_enable_device(struct da9052_tsi *tsi) +{

• ssize_t ret;
• struct da9052 *da9052 = tsi->da9052;
• ret = da9052_ts_configure_gpio(tsi->da9052);
• if (ret < 0)

• return ret;
  

• ret = da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 0xFC, 0xC0);
• if (ret < 0)

• return ret;
  

• tsi->valid_penup_count = 5;
• init_completion(&tsi->tsi_pen_state_thread.notifier);
• tsi->tsi_pen_state_thread.state = DA9052_ACTIVE;
• tsi->tsi_pen_state_thread.pid = kernel_thread(da9052_ts_monitor_pen_state, tsi,

• 				      CLONE_KERNEL | SIGCHLD);
  

• init_completion(&tsi->tsi_filter_thread.notifier);
• tsi->tsi_filter_thread.state = DA9052_ACTIVE;
• tsi->tsi_filter_thread.pid = kernel_thread(da9052_ts_process_thread, tsi,

• 				   CLONE_KERNEL | SIGCHLD);
  

• tsi->zero_data_cnt = 0;
• /* Measure TSI sample every 1ms */
• ret = da9052_reg_update(tsi->da9052, DA9052_ADC_CONT_REG,

• 		1 << 6, 1 << 6);
  

• if (ret < 0)

• return ret;
  

• /* TSI_DELAY: 4 slots, TSI_SKIP: 0 slots, TSI_MODE: XYZP */
• ret = da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG,

• 		1 << 1, 1 << 1);
  

• if (ret < 0)

• return ret;
  

• da9052->events_mask |= DA9052_E_TSI_READY;
• /* Mask TSI_READY event*/
• ret = da9052_reg_update(da9052, DA9052_IRQ_MASK_B_REG, 0, 0x80);
• if (ret < 0)

• return ret;
  

• /*Supply TSIRef thru LD09 */
• ret = da9052_reg_write(tsi->da9052, DA9052_LDO9_REG, 0x59);
• return ret;

+}

+static s32 __devinit da9052_ts_probe(struct platform_device *pdev) +{

• struct da9052_tsi *tsi;
• struct input_dev *input_dev;
• struct da9052 *da9052;
• int ret;
• da9052 = dev_get_drvdata(pdev->dev.parent);

Check for NULL?

• tsi = kzalloc(sizeof(struct da9052_tsi), GFP_KERNEL);
• if (!tsi)

• return -ENOMEM;
  

• input_dev = input_allocate_device();
• if (!input_dev) {

• dev_err(tsi->da9052->dev,
  

• 	"failed to allocate input device\n");
  

• ret = -ENOMEM;
  

• goto err_mem;
  

• }
• ret = kfifo_alloc(&tsi->fifo, DA9052_TSI_FIFOSIZE, GFP_KERNEL);
• if (ret < 0)

• goto err_input;
  

• ret = kfifo_alloc(&tsi->fifo_buf, DA9052_TSI_FIFOSIZE, GFP_KERNEL);
• if (ret < 0)

• goto err_fifo;
  

• tsi->da9052 = da9052;
• tsi->pen_up_detect_interval = 5;
• platform_set_drvdata(pdev, tsi);

Can probably be moved right before "return 0;" statement.

• input_dev->id.version = 0x0101;
• input_dev->id.vendor = 0x15B6;
• input_dev->id.product = 0x9052;
• input_dev->id.bustype = BUS_RS232;

Is it really RS232? BUS_HOST or leave it 0.

• input_dev->name = "Dialog DA9052 TouchScreen Driver";
• input_dev->dev.parent = &pdev->dev;
• __set_bit(EV_ABS, input_dev->evbit);
• __set_bit(EV_KEY, input_dev->evbit);
• __set_bit(BTN_TOUCH, input_dev->keybit);
• __set_bit(ABS_X, input_dev->absbit);
• __set_bit(ABS_Y, input_dev->absbit);
• input_set_abs_params(input_dev, ABS_X, 0, 1023, 0, 0);
• input_set_abs_params(input_dev, ABS_Y, 0, 1023, 0, 0);
• input_set_abs_params(input_dev, ABS_PRESSURE, 0, 1023, 0, 0);
• tsi->dev = input_dev;
• input_set_drvdata(input_dev, tsi);

I do not think you are using input_get_drvdata() enywhere...

• ret = input_register_device(tsi->dev);
• if (ret)

• goto err_mem;
  

• tsi->irq_pendwn = platform_get_irq_byname(pdev, "PENDWN");

What if call fails?

• ret = request_threaded_irq(tsi->da9052->irq_base + tsi->irq_pendwn,

• 		NULL, da9052_ts_pendwn_irq,
  

• 		IRQF_TRIGGER_LOW | IRQF_ONESHOT,
  

• 		"PENDWN", tsi);
  

• if (ret < 0) {

• dev_err(tsi->da9052->dev,
  

• 	"Failed to register %s IRQ %d, error = %d\n", "PENDWN",
  

• 	tsi->da9052->irq_base + tsi->irq_pendwn, ret);
  

• goto err_fifo_buf;
  

• }
• tsi->irq_datardy = platform_get_irq_byname(pdev, "TSIRDY");
• ret = request_threaded_irq(tsi->da9052->irq_base + tsi->irq_datardy,

• 		NULL, da9052_ts_datardy_irq,
  

• 		IRQF_TRIGGER_LOW | IRQF_ONESHOT,
  

• 		"TSIRDY", tsi);
  

• if (ret < 0) {

• dev_err(tsi->da9052->dev,
  

• 	"Failed to register %s IRQ %d, error = %d\n", "TSIRDY",
  

• 	tsi->da9052->irq_base + tsi->irq_datardy, ret);
  

• goto err_fifo_buf;
  

• }
• ret = da9052_ts_enable_device(tsi);
• if (ret < 0)

• goto err_fifo_buf;
  

• return 0;

+err_fifo_buf:

Error handling is busted, you forgetting to free IRQs.

• kfifo_free(&tsi->fifo_buf);

+err_fifo:

• kfifo_free(&tsi->fifo);

+err_input:

Sometimes device is already registered here, you need to call input_unregister_device() in such cases. The easiest way to handle this case it to register input device as the very last action.

• input_free_device(input_dev);

+err_mem:

• kfree(tsi);
• return ret;

+}

+static int __devexit da9052_ts_remove(struct platform_device *pdev) +{

• struct da9052_tsi *tsi = platform_get_drvdata(pdev);
• s32 ret;
• ret = da9052_clear_bits(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 0);
• if (ret < 0)

• return ret;
  

• ret = da9052_reg_write(tsi->da9052, DA9052_LDO9_REG, 0x19);
• if (ret < 0)

• return ret;
  

• free_irq(tsi->da9052->irq_base + tsi->irq_pendwn, NULL);
• free_irq(tsi->da9052->irq_base + tsi->irq_datardy, NULL);

You passed 'tsi' to request_irq(), here you are passing NULL thus leaking IRQs.

• tsi->tsi_pen_state_thread.state = DA9052_INACTIVE;
• wait_for_completion(&tsi->tsi_pen_state_thread.notifier);
• tsi->tsi_filter_thread.state = DA9052_INACTIVE;
• wait_for_completion(&tsi->tsi_filter_thread.notifier);
• input_unregister_device(tsi->dev);
• platform_set_drvdata(pdev, NULL);
• kfifo_free(&tsi->fifo);
• kfifo_free(&tsi->fifo_buf);
• kfree(tsi);
• return 0;

+}

+static struct platform_driver da9052_tsi_driver = {

• .probe = da9052_ts_probe,
• .remove = __devexit_p(da9052_ts_remove),
• .driver = {

• .name = "da9052-tsi",
  

• .owner = THIS_MODULE,
  

• },

+};

+static int __init da9052_ts_init(void) +{

• return platform_driver_register(&da9052_tsi_driver);

+} +module_init(da9052_ts_init);

+static void __exit da9052_ts_exit(void) +{

• platform_driver_unregister(&da9052_tsi_driver);

+} +module_exit(da9052_ts_exit);

+MODULE_DESCRIPTION("Touchscreen driver for Dialog Semiconductor DA9052"); +MODULE_AUTHOR("David Dajun Chen dchen@diasemi.com"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:da9052-tsi");

Thanks.