[PATCH v3 2/2] touchscreen: goodix: define GPIO mapping for GPD P2 Max

From: Peter Cai <peter@typeblog.net>
To: unlisted-recipients:; (no To-header on input)
Cc: Peter Cai <peter@typeblog.net>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Mika Westerberg <mika.westerberg@linux.intel.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	Bastien Nocera <hadess@hadess.net>,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	linux-gpio@vger.kernel.org, linux-acpi@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-input@vger.kernel.org
Subject: [PATCH v3 2/2] touchscreen: goodix: define GPIO mapping for GPD P2 Max
Date: Mon,  2 Sep 2019 20:43:52 +0800	[thread overview]
Message-ID: <20190902124352.12291-2-peter@typeblog.net> (raw)
In-Reply-To: <20190902124352.12291-1-peter@typeblog.net>

The firmware of GPD P2 Max could not handle panel resets although code
is present in DSDT. The kernel needs to take on this job instead, but
the DSDT does not provide _DSD, rendering kernel helpless when trying to
find the respective GPIO pins.

Fortunately, this time GPD has proper DMI vendor / product strings that
we could match against. We simply apply an acpi_gpio_mapping table when
GPD P2 Max is matched.

Additionally, the DSDT definition of the irq pin specifies a wrong
polarity. The new quirk introduced in the previous patch
(ACPI_GPIO_QUIRK_OVERRIDE_POLARITY) is applied to correct this.

Signed-off-by: Peter Cai <peter@typeblog.net>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---

v2: removed '#ifdef CONFIG_ACPI' as per suggestion. The #ifdef guards
for CONFIG_DMI is kept for consistency with the other dmi_system_id
definition in the same file.

v3: minor style adjustments. Added 'const' to dmi_match and moved it in
reverse xmas tree order as per suggestion.
---
 drivers/input/touchscreen/goodix.c | 31 ++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
index 5178ea8b5f30..49ce478c1134 100644
--- a/drivers/input/touchscreen/goodix.c
+++ b/drivers/input/touchscreen/goodix.c
@@ -144,6 +144,31 @@ static const struct dmi_system_id rotated_screen[] = {
 	{}
 };
 
+static const struct acpi_gpio_params irq_gpios_default = { 0, 0, false };
+static const struct acpi_gpio_params reset_gpios_default = { 1, 0, false };
+static const struct acpi_gpio_mapping gpio_mapping_force_irq_active_high[] = {
+	{ "irq-gpios", &irq_gpios_default, 1, ACPI_GPIO_QUIRK_OVERRIDE_POLARITY },
+	{ "reset-gpios", &reset_gpios_default, 1 },
+	{}
+};
+
+/*
+ * Devices that need acpi_gpio_mapping to function correctly
+ */
+static const struct dmi_system_id need_gpio_mapping[] = {
+#if defined(CONFIG_DMI) && defined(CONFIG_X86)
+	{
+		.ident = "GPD P2 Max",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "P2 MAX")
+		},
+		.driver_data = &gpio_mapping_force_irq_active_high
+	},
+#endif
+	{}
+};
+
 /**
  * goodix_i2c_read - read data from a register of the i2c slave device.
  *
@@ -793,9 +818,15 @@ static void goodix_disable_regulators(void *arg)
 static int goodix_ts_probe(struct i2c_client *client,
 			   const struct i2c_device_id *id)
 {
+	const struct dmi_system_id *dmi_match;
 	struct goodix_ts_data *ts;
 	int error;
 
+	dmi_match = dmi_first_match(need_gpio_mapping);
+	if (dmi_match)
+		devm_acpi_dev_add_driver_gpios(&client->dev,
+					       dmi_match->driver_data);
+
 	dev_dbg(&client->dev, "I2C Address: 0x%02x\n", client->addr);
 
 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
-- 
2.23.0

