linux-kernel - [PATCH RFT v7 6/6] input: ads7846: Move wait_for

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20231009-pxa-gpio-v7-6-c8f5f403e856@skole.hr>
Date:   Mon, 09 Oct 2023 20:34:03 +0200
From:   Duje Mihanović <duje.mihanovic@...le.hr>
To:     Daniel Mack <daniel@...que.org>,
        Haojian Zhuang <haojian.zhuang@...il.com>,
        Robert Jarzmik <robert.jarzmik@...e.fr>,
        Russell King <linux@...linux.org.uk>,
        Alan Stern <stern@...land.harvard.edu>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Linus Walleij <linus.walleij@...aro.org>,
        Bartosz Golaszewski <brgl@...ev.pl>,
        Andy Shevchenko <andy@...nel.org>,
        Dmitry Torokhov <dmitry.torokhov@...il.com>,
        Mark Brown <broonie@...nel.org>
Cc:     linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-usb@...r.kernel.org, linux-gpio@...r.kernel.org,
        linux-input@...r.kernel.org, linux-spi@...r.kernel.org,
        Duje Mihanović <duje.mihanovic@...le.hr>,
        Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Subject: [PATCH RFT v7 6/6] input: ads7846: Move wait_for_sync() logic to
 driver

If this code is left in the board file, the sync GPIO would have to be
separated into another lookup table during conversion to the GPIO
descriptor API (which is also done in this patch).

The only user of this code (Sharp Spitz) is also converted in this
patch.

Suggested-by: Linus Walleij <linus.walleij@...aro.org>
Reviewed-by: Linus Walleij <linus.walleij@...aro.org>
Acked-by: Mark Brown <broonie@...nel.org>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Signed-off-by: Duje Mihanović <duje.mihanovic@...le.hr>
---
 arch/arm/mach-pxa/spitz.c           | 12 ++----------
 drivers/input/touchscreen/ads7846.c | 22 +++++++++++++++-------
 include/linux/spi/ads7846.h         |  1 -
 3 files changed, 17 insertions(+), 18 deletions(-)

diff --git a/arch/arm/mach-pxa/spitz.c b/arch/arm/mach-pxa/spitz.c
index 4b6360821396..44336a498699 100644
--- a/arch/arm/mach-pxa/spitz.c
+++ b/arch/arm/mach-pxa/spitz.c
@@ -522,22 +522,12 @@ static inline void spitz_leds_init(void) {}
  * SSP Devices
  ******************************************************************************/
 #if defined(CONFIG_SPI_PXA2XX) || defined(CONFIG_SPI_PXA2XX_MODULE)
-static void spitz_ads7846_wait_for_hsync(void)
-{
-	while (gpio_get_value(SPITZ_GPIO_HSYNC))
-		cpu_relax();
-
-	while (!gpio_get_value(SPITZ_GPIO_HSYNC))
-		cpu_relax();
-}
-
 static struct ads7846_platform_data spitz_ads7846_info = {
 	.model			= 7846,
 	.vref_delay_usecs	= 100,
 	.x_plate_ohms		= 419,
 	.y_plate_ohms		= 486,
 	.pressure_max		= 1024,
-	.wait_for_sync		= spitz_ads7846_wait_for_hsync,
 };
 
 static struct gpiod_lookup_table spitz_ads7846_gpio_table = {
@@ -545,6 +535,8 @@ static struct gpiod_lookup_table spitz_ads7846_gpio_table = {
 	.table = {
 		GPIO_LOOKUP("gpio-pxa", SPITZ_GPIO_TP_INT,
 			    "pendown", GPIO_ACTIVE_LOW),
+		GPIO_LOOKUP("gpio-pxa", SPITZ_GPIO_HSYNC,
+			    "sync", GPIO_ACTIVE_LOW),
 		{ }
 	},
 };
diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index faea40dd66d0..139b0f3735d0 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -138,8 +138,7 @@ struct ads7846 {
 	void			*filter_data;
 	int			(*get_pendown_state)(void);
 	struct gpio_desc	*gpio_pendown;
-
-	void			(*wait_for_sync)(void);
+	struct gpio_desc	*sync;
 };
 
 enum ads7846_filter {
@@ -636,9 +635,15 @@ static const struct attribute_group ads784x_attr_group = {
 };
 
 /*--------------------------------------------------------------------------*/
-
-static void null_wait_for_sync(void)
+static void ads7846_wait_for_sync_gpio(struct ads7846 *ts)
 {
+	if (!ts->sync)
+		return;
+	while (!gpiod_get_value(ts->sync))
+		cpu_relax();
+
+	while (gpiod_get_value(ts->sync))
+		cpu_relax();
 }
 
 static int ads7846_debounce_filter(void *ads, int data_idx, int *val)
@@ -803,7 +808,7 @@ static void ads7846_read_state(struct ads7846 *ts)
 	packet->last_cmd_idx = 0;
 
 	while (true) {
-		ts->wait_for_sync();
+		ads7846_wait_for_sync_gpio(ts);
 
 		m = &ts->msg[msg_idx];
 		error = spi_sync(ts->spi, m);
@@ -1261,8 +1266,6 @@ static int ads7846_probe(struct spi_device *spi)
 		ts->penirq_recheck_delay_usecs =
 				pdata->penirq_recheck_delay_usecs;
 
-	ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync;
-
 	snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
 	snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model);
 
@@ -1361,6 +1364,11 @@ static int ads7846_probe(struct spi_device *spi)
 	if (err)
 		return err;
 
+	ts->sync = devm_gpiod_get_optional(dev, "sync", GPIOD_IN);
+	if (IS_ERR(ts->sync))
+		return dev_err_probe(dev, PTR_ERR(ts->sync),
+				"Failed to get sync GPIO");
+
 	err = input_register_device(input_dev);
 	if (err)
 		return err;
diff --git a/include/linux/spi/ads7846.h b/include/linux/spi/ads7846.h
index a04c1c34c344..fa7c4f119023 100644
--- a/include/linux/spi/ads7846.h
+++ b/include/linux/spi/ads7846.h
@@ -38,7 +38,6 @@ struct ads7846_platform_data {
 	int	gpio_pendown_debounce;	/* platform specific debounce time for
 					 * the gpio_pendown */
 	int	(*get_pendown_state)(void);
-	void	(*wait_for_sync)(void);
 	bool	wakeup;
 	unsigned long irq_flags;
 };

-- 
2.42.0