Re: [Patch 07/07] Touch: DA9052/53 touch screen driver v1

From: Dmitry Torokhov
Date: Sun Mar 18 2012 - 00:06:05 EST


Hi Ashish,

On Tue, Mar 13, 2012 at 05:55:06PM +0530, Ashish Jangam wrote:
> Any update on the below patch

I looked the patch over and I think that the disabling of the IRQs in
da9052_ts_input_close() is racy. You can't read device status and
disable one IRQ or another as pendwn IRQ may fire right after you read
the register and you will disable the wrong one.

I tried correcting this problem and also did some more cosmetic changes,
could you please try the patch below and let me know if it works for
you?

Thanks!

--
Dmitry


Input: add support for DA9052/53 touch screen controller

From: Ashish Jangam <ashish.jangam@xxxxxxxxxxxxxxx>

This driver adds support for DA9052/53 4-wire resistive ADC interfaced
touchscreen controller. DA9052/53 is a multi-function device, therefore
this driver depends on DA9052/53 core.

This patch is functionally tested on Samsung SMDKV6410.

Signed-off-by: David Dajun Chen <dchen@xxxxxxxxxxx>
Signed-off-by: Ashish Jangam <ashish.jangam@xxxxxxxxxxxxxxx>
Signed-off-by: Dmitry Torokhov <dtor@xxxxxxx>
---

drivers/input/touchscreen/Kconfig | 17 ++
drivers/input/touchscreen/Makefile | 1
drivers/input/touchscreen/da9052_tsi.c | 361 ++++++++++++++++++++++++++++++++
3 files changed, 379 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/da9052_tsi.c


diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 97b31a0..3594591 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -187,6 +187,23 @@ config TOUCHSCREEN_DA9034
Say Y here to enable the support for the touchscreen found
on Dialog Semiconductor DA9034 PMIC.

+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called da9034-ts.
+
+config TOUCHSCREEN_DA9052
+ tristate "Dialog DA9052/DA9053 TSI"
+ depends on PMIC_DA9052
+ help
+ Say Y here to support the touchscreen found on Dialog Semiconductor
+ DA9052-BC and DA9053-AA/Bx PMICs.
+
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called da9052_tsi.
+
config TOUCHSCREEN_DYNAPRO
tristate "Dynapro serial touchscreen"
select SERIO
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 3d5cf8c..b6c746e0 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_TOUCHSCREEN_CYTTSP_CORE) += cyttsp_core.o
obj-$(CONFIG_TOUCHSCREEN_CYTTSP_I2C) += cyttsp_i2c.o
obj-$(CONFIG_TOUCHSCREEN_CYTTSP_SPI) += cyttsp_spi.o
obj-$(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 100644
index 0000000..76fad0e
--- /dev/null
+++ b/drivers/input/touchscreen/da9052_tsi.c
@@ -0,0 +1,361 @@
+/*
+ * TSI driver for Dialog DA9052
+ *
+ * Copyright(c) 2012 Dialog Semiconductor Ltd.
+ *
+ * Author: David Dajun Chen <dchen@xxxxxxxxxxx>
+ *
+ * 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/interrupt.h>
+
+#include <linux/mfd/da9052/reg.h>
+#include <linux/mfd/da9052/da9052.h>
+
+#define TSI_PEN_DOWN_STATUS 0x40
+
+struct da9052_tsi {
+ struct da9052 *da9052;
+ struct input_dev *dev;
+ struct delayed_work ts_pen_work;
+ struct mutex mutex;
+ unsigned int irq_pendwn;
+ unsigned int irq_datardy;
+ bool stopped;
+ bool adc_on;
+};
+
+static void da9052_ts_adc_toggle(struct da9052_tsi *tsi, bool on)
+{
+ da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 0, on);
+ tsi->adc_on = on;
+}
+
+static irqreturn_t da9052_ts_pendwn_irq(int irq, void *data)
+{
+ struct da9052_tsi *tsi = data;
+
+ if (!tsi->stopped) {
+ /* Mask PEN_DOWN event and unmask TSI_READY event */
+ disable_irq_nosync(tsi->irq_pendwn);
+ enable_irq(tsi->irq_datardy);
+
+ da9052_ts_adc_toggle(tsi, true);
+
+ schedule_delayed_work(&tsi->ts_pen_work, HZ / 50);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void da9052_ts_read(struct da9052_tsi *tsi)
+{
+ struct input_dev *input = tsi->dev;
+ int ret;
+ u16 x, y, z;
+ u8 v;
+
+ ret = da9052_reg_read(tsi->da9052, DA9052_TSI_X_MSB_REG);
+ if (ret < 0)
+ return;
+
+ x = (u16) ret;
+
+ ret = da9052_reg_read(tsi->da9052, DA9052_TSI_Y_MSB_REG);
+ if (ret < 0)
+ return;
+
+ y = (u16) ret;
+
+ ret = da9052_reg_read(tsi->da9052, DA9052_TSI_Z_MSB_REG);
+ if (ret < 0)
+ return;
+
+ z = (u16) ret;
+
+ ret = da9052_reg_read(tsi->da9052, DA9052_TSI_LSB_REG);
+ if (ret < 0)
+ return;
+
+ v = (u8) ret;
+
+ x = ((x << 2) & 0x3fc) | (v & 0x3);
+ y = ((y << 2) & 0x3fc) | ((v & 0xc) >> 2);
+ z = ((z << 2) & 0x3fc) | ((v & 0x30) >> 4);
+
+ input_report_key(input, BTN_TOUCH, 1);
+ input_report_abs(input, ABS_X, x);
+ input_report_abs(input, ABS_Y, y);
+ input_report_abs(input, ABS_PRESSURE, z);
+ input_sync(input);
+}
+
+static irqreturn_t da9052_ts_datardy_irq(int irq, void *data)
+{
+ struct da9052_tsi *tsi = data;
+
+ da9052_ts_read(tsi);
+
+ return IRQ_HANDLED;
+}
+
+static void da9052_ts_pen_work(struct work_struct *work)
+{
+ struct da9052_tsi *tsi = container_of(work, struct da9052_tsi,
+ ts_pen_work.work);
+ if (!tsi->stopped) {
+ int ret = da9052_reg_read(tsi->da9052, DA9052_TSI_LSB_REG);
+ if (ret < 0 || (ret & TSI_PEN_DOWN_STATUS)) {
+ /* Pen is still DOWN (or read error) */
+ schedule_delayed_work(&tsi->ts_pen_work, HZ / 50);
+ } else {
+ struct input_dev *input = tsi->dev;
+
+ /* Pen UP */
+ da9052_ts_adc_toggle(tsi, false);
+
+ /* Report Pen UP */
+ input_report_key(input, BTN_TOUCH, 0);
+ input_report_abs(input, ABS_PRESSURE, 0);
+ input_sync(input);
+
+ /* Mask TSI_READY event and unmask PEN_DOWN event */
+ disable_irq(tsi->irq_datardy);
+ enable_irq(tsi->irq_pendwn);
+ }
+ }
+}
+
+static int __devinit da9052_ts_configure_gpio(struct da9052 *da9052)
+{
+ int error;
+
+ error = da9052_reg_update(da9052, DA9052_GPIO_2_3_REG, 0x30, 0);
+ if (error < 0)
+ return error;
+
+ error = da9052_reg_update(da9052, DA9052_GPIO_4_5_REG, 0x33, 0);
+ if (error < 0)
+ return error;
+
+ error = da9052_reg_update(da9052, DA9052_GPIO_6_7_REG, 0x33, 0);
+ if (error < 0)
+ return error;
+
+ return 0;
+}
+
+static int __devinit da9052_configure_tsi(struct da9052_tsi *tsi)
+{
+ int error;
+
+ error = da9052_ts_configure_gpio(tsi->da9052);
+ if (error)
+ return error;
+
+ /* Measure TSI sample every 1ms */
+ error = da9052_reg_update(tsi->da9052, DA9052_ADC_CONT_REG,
+ 1 << 6, 1 << 6);
+ if (error < 0)
+ return error;
+
+ /* TSI_DELAY: 3 slots, TSI_SKIP: 0 slots, TSI_MODE: XYZP */
+ error = da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 0xFC, 0xC0);
+ if (error < 0)
+ return error;
+
+ /* Supply TSIRef through LD09 */
+ error = da9052_reg_write(tsi->da9052, DA9052_LDO9_REG, 0x59);
+ if (error < 0)
+ return error;
+
+ return 0;
+}
+
+static int da9052_ts_input_open(struct input_dev *input_dev)
+{
+ struct da9052_tsi *tsi = input_get_drvdata(input_dev);
+
+ tsi->stopped = false;
+ mb();
+
+ /* Unmask PEN_DOWN event */
+ enable_irq(tsi->irq_pendwn);
+
+ /* Enable Pen Detect Circuit */
+ return da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG,
+ 1 << 1, 1 << 1);
+}
+
+static void da9052_ts_input_close(struct input_dev *input_dev)
+{
+ struct da9052_tsi *tsi = input_get_drvdata(input_dev);
+
+ tsi->stopped = true;
+ mb();
+ disable_irq(tsi->irq_pendwn);
+ cancel_delayed_work_sync(&tsi->ts_pen_work);
+
+ if (tsi->adc_on) {
+ disable_irq(tsi->irq_datardy);
+ da9052_ts_adc_toggle(tsi, false);
+
+ /*
+ * If ADC was on that means that pendwn IRQ was disabled
+ * twice and we need to enable it to keep enable/disable
+ * counter balanced. IRQ is still off though.
+ */
+ enable_irq(tsi->irq_pendwn);
+ }
+
+ /* Disable Pen Detect Circuit */
+ da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 1, 0);
+}
+
+static int __devinit da9052_ts_probe(struct platform_device *pdev)
+{
+ struct da9052 *da9052;
+ struct da9052_tsi *tsi;
+ struct input_dev *input_dev;
+ int irq_pendwn;
+ int irq_datardy;
+ int error;
+
+ da9052 = dev_get_drvdata(pdev->dev.parent);
+ if (!da9052)
+ return -EINVAL;
+
+ irq_pendwn = platform_get_irq_byname(pdev, "PENDWN");
+ irq_datardy = platform_get_irq_byname(pdev, "TSIRDY");
+ if (irq_pendwn < 0 || irq_datardy < 0) {
+ dev_err(da9052->dev, "Unable to determine device interrupts\n");
+ return -ENXIO;
+ }
+
+ tsi = kzalloc(sizeof(struct da9052_tsi), GFP_KERNEL);
+ input_dev = input_allocate_device();
+ if (!tsi || !input_dev) {
+ error = -ENOMEM;
+ goto err_free_mem;
+ }
+
+ tsi->da9052 = da9052;
+ tsi->dev = input_dev;
+ tsi->irq_pendwn = irq_pendwn;
+ tsi->irq_datardy = irq_datardy;
+ tsi->stopped = true;
+ INIT_DELAYED_WORK(&tsi->ts_pen_work, da9052_ts_pen_work);
+
+ input_dev->id.version = 0x0101;
+ input_dev->id.vendor = 0x15B6;
+ input_dev->id.product = 0x9052;
+ input_dev->name = "Dialog DA9052 TouchScreen Driver";
+ input_dev->dev.parent = &pdev->dev;
+ input_dev->open = da9052_ts_input_open;
+ input_dev->close = da9052_ts_input_close;
+
+ __set_bit(EV_ABS, input_dev->evbit);
+ __set_bit(EV_KEY, input_dev->evbit);
+ __set_bit(BTN_TOUCH, input_dev->keybit);
+
+ 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);
+
+ input_set_drvdata(input_dev, tsi);
+
+ /* Disable Pen Detect Circuit */
+ da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 1, 0);
+
+ /* Disable ADC */
+ da9052_ts_adc_toggle(tsi, true);
+
+ error = request_threaded_irq(tsi->irq_pendwn,
+ NULL, da9052_ts_pendwn_irq,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ "PENDWN", tsi);
+ if (error) {
+ dev_err(tsi->da9052->dev,
+ "Failed to register PENDWN IRQ %d, error = %d\n",
+ tsi->irq_pendwn, error);
+ goto err_free_mem;
+ }
+
+ error = request_threaded_irq(tsi->irq_datardy,
+ NULL, da9052_ts_datardy_irq,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ "TSIRDY", tsi);
+ if (error) {
+ dev_err(tsi->da9052->dev,
+ "Failed to register TSIRDY IRQ %d, error = %d\n",
+ tsi->irq_datardy, error);
+ goto err_free_pendwn_irq;
+ }
+
+ /* Mask PEN_DOWN and TSI_READY events */
+ disable_irq(tsi->irq_pendwn);
+ disable_irq(tsi->irq_datardy);
+
+ error = da9052_configure_tsi(tsi);
+ if (error)
+ goto err_free_datardy_irq;
+
+ error = input_register_device(tsi->dev);
+ if (error)
+ goto err_free_datardy_irq;
+
+ platform_set_drvdata(pdev, tsi);
+
+ return 0;
+
+err_free_datardy_irq:
+ free_irq(tsi->irq_datardy, tsi);
+err_free_pendwn_irq:
+ free_irq(tsi->irq_pendwn, tsi);
+err_free_mem:
+ kfree(tsi);
+ input_free_device(input_dev);
+
+ return error;
+}
+
+static int __devexit da9052_ts_remove(struct platform_device *pdev)
+{
+ struct da9052_tsi *tsi = platform_get_drvdata(pdev);
+
+ da9052_reg_write(tsi->da9052, DA9052_LDO9_REG, 0x19);
+
+ free_irq(tsi->irq_pendwn, tsi);
+ free_irq(tsi->irq_datardy, tsi);
+
+ input_unregister_device(tsi->dev);
+ kfree(tsi);
+
+ platform_set_drvdata(pdev, NULL);
+
+ 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,
+ },
+};
+
+module_platform_driver(da9052_tsi_driver);
+
+MODULE_DESCRIPTION("Touchscreen driver for Dialog Semiconductor DA9052");
+MODULE_AUTHOR("David Dajun Chen <dchen@xxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:da9052-tsi");
--
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