Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758385AbbKSM2K (ORCPT ); Thu, 19 Nov 2015 07:28:10 -0500 Received: from mga11.intel.com ([192.55.52.93]:44120 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751104AbbKSM2G (ORCPT ); Thu, 19 Nov 2015 07:28:06 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,317,1444719600"; d="scan'208";a="824010495" From: Irina Tirdea To: Dmitry Torokhov , Bastien Nocera , Aleksei Mamlin , Karsten Merker , linux-input@vger.kernel.org Cc: Mark Rutland , Rob Herring , Octavian Purdila , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Irina Tirdea Subject: [PATCH v11 2/8] Input: goodix - reset device at init Date: Thu, 19 Nov 2015 14:26:35 +0200 Message-Id: <1447936001-21420-3-git-send-email-irina.tirdea@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1447936001-21420-1-git-send-email-irina.tirdea@intel.com> References: <1447936001-21420-1-git-send-email-irina.tirdea@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7892 Lines: 260 After power on, it is recommended that the driver resets the device. The reset procedure timing is described in the datasheet and is used at device init (before writing device configuration) and for power management. It is a sequence of setting the interrupt and reset pins high/low at specific timing intervals. This procedure also includes setting the slave address to the one specified in the ACPI/device tree. This is based on Goodix datasheets for GT911 and GT9271 and on Goodix driver gt9xx.c for Android (publicly available in Android kernel trees for various devices). For reset the driver needs to control the interrupt and reset gpio pins (configured through ACPI/device tree). For devices that do not have the gpio pins properly declared, the functionality depending on these pins will not be available, but the device can still be used with basic functionality. For both device tree and ACPI, the interrupt gpio pin configuration is read from the "irq-gpios" property and the reset pin configuration is read from the "reset-gpios" property. For ACPI 5.1, named properties can be specified using the _DSD section. This functionality will not be available for devices that use indexed gpio pins declared in the _CRS section (we need to provide backward compatibility with devices that do not support using the interrupt gpio pin as output). For ACPI, the pins can be specified using ACPI 5.1: Device (STAC) { Name (_HID, "GDIX1001") ... Method (_CRS, 0, Serialized) { Name (RBUF, ResourceTemplate () { I2cSerialBus (0x0014, ControllerInitiated, 0x00061A80, AddressingMode7Bit, "\\I2C0", 0x00, ResourceConsumer, , ) GpioInt (Edge, ActiveHigh, Exclusive, PullNone, 0x0000, "\\I2C0", 0x00, ResourceConsumer, , ) { // Pin list 0 } GpioIo (Exclusive, PullDown, 0x0000, 0x0000, IoRestrictionOutputOnly, "\\I2C0", 0x00, ResourceConsumer, , ) { 1 } }) Return (RBUF) } Name (_DSD, Package () { ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), Package () { Package (2) {"irq-gpios", Package() {^STAC, 0, 0, 0 }}, Package (2) {"reset-gpios", Package() {^STAC, 1, 0, 0 }}, ... } } Signed-off-by: Octavian Purdila Signed-off-by: Irina Tirdea --- .../bindings/input/touchscreen/goodix.txt | 9 ++ drivers/input/touchscreen/Kconfig | 1 + drivers/input/touchscreen/goodix.c | 101 +++++++++++++++++++++ 3 files changed, 111 insertions(+) diff --git a/Documentation/devicetree/bindings/input/touchscreen/goodix.txt b/Documentation/devicetree/bindings/input/touchscreen/goodix.txt index 8ba98ee..c42d2ce 100644 --- a/Documentation/devicetree/bindings/input/touchscreen/goodix.txt +++ b/Documentation/devicetree/bindings/input/touchscreen/goodix.txt @@ -13,6 +13,12 @@ Required properties: - interrupt-parent : Interrupt controller to which the chip is connected - interrupts : Interrupt to which the chip is connected +Optional properties: + + - irq-gpios : GPIO pin used for IRQ. The driver uses the + interrupt gpio pin as output to reset the device. + - reset-gpios : GPIO pin used for reset + Example: i2c@00000000 { @@ -23,6 +29,9 @@ Example: reg = <0x5d>; interrupt-parent = <&gpio>; interrupts = <0 0>; + + irq-gpios = <&gpio1 0 0>; + reset-gpios = <&gpio1 1 0>; }; /* ... */ diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig index 2ccc522..121a0ac 100644 --- a/drivers/input/touchscreen/Kconfig +++ b/drivers/input/touchscreen/Kconfig @@ -324,6 +324,7 @@ config TOUCHSCREEN_FUJITSU config TOUCHSCREEN_GOODIX tristate "Goodix I2C touchscreen" depends on I2C + depends on GPIOLIB help Say Y here if you have the Goodix touchscreen (such as one installed in Onda v975w tablets) connected to your diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c index 56d0330..4744032 100644 --- a/drivers/input/touchscreen/goodix.c +++ b/drivers/input/touchscreen/goodix.c @@ -16,6 +16,7 @@ #include #include +#include #include #include #include @@ -37,8 +38,13 @@ struct goodix_ts_data { unsigned int int_trigger_type; bool rotated_screen; int cfg_len; + struct gpio_desc *gpiod_int; + struct gpio_desc *gpiod_rst; }; +#define GOODIX_GPIO_INT_NAME "irq" +#define GOODIX_GPIO_RST_NAME "reset" + #define GOODIX_MAX_HEIGHT 4096 #define GOODIX_MAX_WIDTH 4096 #define GOODIX_INT_TRIGGER 1 @@ -237,6 +243,88 @@ static irqreturn_t goodix_ts_irq_handler(int irq, void *dev_id) return IRQ_HANDLED; } +static int goodix_int_sync(struct goodix_ts_data *ts) +{ + int error; + + error = gpiod_direction_output(ts->gpiod_int, 0); + if (error) + return error; + msleep(50); /* T5: 50ms */ + + return gpiod_direction_input(ts->gpiod_int); +} + +/** + * goodix_reset - Reset device during power on + * + * @ts: goodix_ts_data pointer + */ +static int goodix_reset(struct goodix_ts_data *ts) +{ + int error; + + /* begin select I2C slave addr */ + error = gpiod_direction_output(ts->gpiod_rst, 0); + if (error) + return error; + msleep(20); /* T2: > 10ms */ + /* HIGH: 0x28/0x29, LOW: 0xBA/0xBB */ + error = gpiod_direction_output(ts->gpiod_int, ts->client->addr == 0x14); + if (error) + return error; + usleep_range(100, 2000); /* T3: > 100us */ + error = gpiod_direction_output(ts->gpiod_rst, 1); + if (error) + return error; + usleep_range(6000, 10000); /* T4: > 5ms */ + /* end select I2C slave addr */ + error = gpiod_direction_input(ts->gpiod_rst); + if (error) + return error; + return goodix_int_sync(ts); +} + +/** + * goodix_get_gpio_config - Get GPIO config from ACPI/DT + * + * @ts: goodix_ts_data pointer + */ +static int goodix_get_gpio_config(struct goodix_ts_data *ts) +{ + int error; + struct device *dev; + struct gpio_desc *gpiod; + + if (!ts->client) + return -EINVAL; + dev = &ts->client->dev; + + /* Get the interrupt GPIO pin number */ + gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_INT_NAME, GPIOD_IN); + if (IS_ERR(gpiod)) { + error = PTR_ERR(gpiod); + if (error != -EPROBE_DEFER) + dev_dbg(dev, "Failed to get %s GPIO: %d\n", + GOODIX_GPIO_INT_NAME, error); + return error; + } + ts->gpiod_int = gpiod; + + /* Get the reset line GPIO pin number */ + gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_RST_NAME, GPIOD_IN); + if (IS_ERR(gpiod)) { + error = PTR_ERR(gpiod); + if (error != -EPROBE_DEFER) + dev_dbg(dev, "Failed to get %s GPIO: %d\n", + GOODIX_GPIO_RST_NAME, error); + return error; + } + ts->gpiod_rst = gpiod; + + return 0; +} + /** * goodix_read_config - Read the embedded configuration of the panel * @@ -405,6 +493,19 @@ static int goodix_ts_probe(struct i2c_client *client, ts->client = client; i2c_set_clientdata(client, ts); + error = goodix_get_gpio_config(ts); + if (error) + return error; + + if (ts->gpiod_int && ts->gpiod_rst) { + /* reset the controller */ + error = goodix_reset(ts); + if (error) { + dev_err(&client->dev, "Controller reset failed.\n"); + return error; + } + } + error = goodix_i2c_test(client); if (error) { dev_err(&client->dev, "I2C communication failure: %d\n", error); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/