Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753295AbbFHOlO (ORCPT ); Mon, 8 Jun 2015 10:41:14 -0400 Received: from mga14.intel.com ([192.55.52.115]:1778 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932111AbbFHOj5 (ORCPT ); Mon, 8 Jun 2015 10:39:57 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,574,1427785200"; d="scan'208";a="743014792" From: Irina Tirdea To: Dmitry Torokhov , Bastien Nocera , Mark Rutland , linux-input@vger.kernel.org, devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Rob Herring , Pawel Moll , Ian Campbell , Kumar Gala , Irina Tirdea , Octavian Purdila Subject: [PATCH v2 4/8] input: goodix: reset device at init Date: Mon, 8 Jun 2015 17:37:49 +0300 Message-Id: <1433774273-23103-5-git-send-email-irina.tirdea@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1433774273-23103-1-git-send-email-irina.tirdea@intel.com> References: <1433774273-23103-1-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: 6437 Lines: 231 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 5.1/device tree). 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-gpio", Package() {^STAC, 0, 0, 0 }}, Package (2) {"reset-gpio", Package() {^STAC, 1, 0, 0 }}, ... } } Signed-off-by: Octavian Purdila Signed-off-by: Irina Tirdea --- .../bindings/input/touchscreen/goodix.txt | 5 ++ drivers/input/touchscreen/goodix.c | 100 +++++++++++++++++++++ 2 files changed, 105 insertions(+) diff --git a/Documentation/devicetree/bindings/input/touchscreen/goodix.txt b/Documentation/devicetree/bindings/input/touchscreen/goodix.txt index 8ba98ee..7137881 100644 --- a/Documentation/devicetree/bindings/input/touchscreen/goodix.txt +++ b/Documentation/devicetree/bindings/input/touchscreen/goodix.txt @@ -12,6 +12,8 @@ Required properties: - reg : I2C address of the chip. Should be 0x5d or 0x14 - interrupt-parent : Interrupt controller to which the chip is connected - interrupts : Interrupt to which the chip is connected + - irq-gpio : GPIO pin used for IRQ + - reset-gpio : GPIO pin used for reset Example: @@ -23,6 +25,9 @@ Example: reg = <0x5d>; interrupt-parent = <&gpio>; interrupts = <0 0>; + + irq-gpio = <&gpio1 0 0>; + reset-gpio = <&gpio1 1 0>; }; /* ... */ diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c index 7cd3780..c345eb7 100644 --- a/drivers/input/touchscreen/goodix.c +++ b/drivers/input/touchscreen/goodix.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include @@ -34,8 +35,13 @@ struct goodix_ts_data { int abs_y_max; unsigned int max_touch_num; unsigned int int_trigger_type; + 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 @@ -186,6 +192,89 @@ 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 ret; + + ret = gpiod_direction_output(ts->gpiod_int, 0); + if (ret) + return ret; + + 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 ret; + + /* begin select I2C slave addr */ + ret = gpiod_direction_output(ts->gpiod_rst, 0); + if (ret) + return ret; + msleep(20); /* T2: > 10ms */ + /* HIGH: 0x28/0x29, LOW: 0xBA/0xBB */ + ret = gpiod_direction_output(ts->gpiod_int, ts->client->addr == 0x14); + if (ret) + return ret; + usleep_range(100, 2000); /* T3: > 100us */ + ret = gpiod_direction_output(ts->gpiod_rst, 1); + if (ret) + return ret; + usleep_range(6000, 10000); /* T4: > 5ms */ + /* end select I2C slave addr */ + ret = gpiod_direction_input(ts->gpiod_rst); + if (ret) + return ret; + ret = goodix_int_sync(ts); + if (ret) + return ret; + msleep(50); /* T5: 50ms */ + return 0; +} + +/** + * 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) +{ + struct device *dev; + struct gpio_desc *gpiod; + int ret; + + if (!ts->client) + return -EINVAL; + dev = &ts->client->dev; + + /* Get interrupt GPIO pin number */ + gpiod = devm_gpiod_get(dev, GOODIX_GPIO_INT_NAME, GPIOD_IN); + if (IS_ERR(gpiod)) { + ret = PTR_ERR(gpiod); + dev_err(dev, "Failed to get %s GPIO: %d\n", + GOODIX_GPIO_INT_NAME, ret); + return ret; + } + ts->gpiod_int = gpiod; + + /* Get the reset line GPIO pin number */ + gpiod = devm_gpiod_get(dev, GOODIX_GPIO_RST_NAME, GPIOD_IN); + if (IS_ERR(gpiod)) { + ret = PTR_ERR(gpiod); + dev_err(dev, "Failed to get %s GPIO: %d\n", + GOODIX_GPIO_RST_NAME, ret); + return ret; + } + ts->gpiod_rst = gpiod; + + return 0; +} + /** * goodix_read_config - Read the embedded configuration of the panel * @@ -365,6 +454,17 @@ static int goodix_ts_probe(struct i2c_client *client, return error; } + error = goodix_get_gpio_config(ts); + if (error) + return error; + + /* reset the controller */ + error = goodix_reset(ts); + if (error) { + dev_err(&client->dev, "Controller reset failed.\n"); + return error; + } + goodix_read_config(ts); error = goodix_request_input_dev(ts, version_info, id_info); -- 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/