From patchwork Sun May 3 17:14:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Artur Rojek X-Patchwork-Id: 11524639 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 54586139A for ; Sun, 3 May 2020 17:06:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 449BD206B9 for ; Sun, 3 May 2020 17:06:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728953AbgECRGC (ORCPT ); Sun, 3 May 2020 13:06:02 -0400 Received: from relay2-d.mail.gandi.net ([217.70.183.194]:45325 "EHLO relay2-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728947AbgECRGB (ORCPT ); Sun, 3 May 2020 13:06:01 -0400 X-Originating-IP: 195.189.32.242 Received: from pc.localdomain (unknown [195.189.32.242]) (Authenticated sender: contact@artur-rojek.eu) by relay2-d.mail.gandi.net (Postfix) with ESMTPSA id EB33C40007; Sun, 3 May 2020 17:05:55 +0000 (UTC) From: Artur Rojek To: Dmitry Torokhov , Rob Herring , Mark Rutland , Jonathan Cameron , Paul Cercueil , Andy Shevchenko Cc: Heiko Stuebner , Ezequiel Garcia , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, Artur Rojek Subject: [PATCH v6 5/7] IIO: Ingenic JZ47xx: Add touchscreen mode. Date: Sun, 3 May 2020 19:14:49 +0200 Message-Id: <20200503171451.44034-5-contact@artur-rojek.eu> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200503171451.44034-1-contact@artur-rojek.eu> References: <20200503171451.44034-1-contact@artur-rojek.eu> MIME-Version: 1.0 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org The SADC component in JZ47xx SoCs provides support for touchscreen operations (pen position and pen down pressure) in single-ended and differential modes. Of the known hardware to use this controller, GCW Zero and Anbernic RG-350 utilize the touchscreen mode by having their joystick(s) attached to the X/Y positive/negative input pins. GCW Zero comes with a single joystick and is sufficiently handled with the currently implemented single-ended mode. Support for boards with two joysticks, where one is hooked up to Xn/Yn and the other to Xp/Yp channels will need to be provided in the future. The touchscreen component of SADC takes a significant time to stabilize after first receiving the clock and a delay of 50ms has been empirically proven to be a safe value before data sampling can begin. All the boards which probe this driver have the interrupt provided from Device Tree, with no need to handle a case where the IRQ was not provided. Signed-off-by: Artur Rojek Tested-by: Paul Cercueil --- Changes: v2: - improve description of the touchscreen mode, - get rid of the unneeded kfifo, - drop IIO_BUFFER_CB from Kconfig, - remove extended names from the touchscreen channels v3: remove unneeded `linux/iio/kfifo_buf.h` include v4: clarify irq provider source in the patch description v5: no change v6: - correct the spelling of Device Tree and IRQ in commit message - don't omit trailing commas from initializer lists - error check `clk_enable` - remove redundant `dev_err` from `platform_get_irq` error check drivers/iio/adc/Kconfig | 1 + drivers/iio/adc/ingenic-adc.c | 115 +++++++++++++++++++++++++++++++++- 2 files changed, 114 insertions(+), 2 deletions(-) diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 12bb8b7ca1ff..c3314135fa2a 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -465,6 +465,7 @@ config INA2XX_ADC config INGENIC_ADC tristate "Ingenic JZ47xx SoCs ADC driver" depends on MIPS || COMPILE_TEST + select IIO_BUFFER help Say yes here to build support for the Ingenic JZ47xx SoCs ADC unit. diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-adc.c index 0eee4b4fb96c..49226d8fd8f6 100644 --- a/drivers/iio/adc/ingenic-adc.c +++ b/drivers/iio/adc/ingenic-adc.c @@ -8,7 +8,9 @@ #include #include +#include #include +#include #include #include #include @@ -20,6 +22,8 @@ #define JZ_ADC_REG_CFG 0x04 #define JZ_ADC_REG_CTRL 0x08 #define JZ_ADC_REG_STATUS 0x0c +#define JZ_ADC_REG_ADSAME 0x10 +#define JZ_ADC_REG_ADWAIT 0x14 #define JZ_ADC_REG_ADTCH 0x18 #define JZ_ADC_REG_ADBDAT 0x1c #define JZ_ADC_REG_ADSDAT 0x20 @@ -28,6 +32,9 @@ #define JZ_ADC_REG_ENABLE_PD BIT(7) #define JZ_ADC_REG_CFG_AUX_MD (BIT(0) | BIT(1)) #define JZ_ADC_REG_CFG_BAT_MD BIT(4) +#define JZ_ADC_REG_CFG_PULL_UP(n) ((n) << 16) +#define JZ_ADC_REG_CFG_SAMPLE_NUM(n) ((n) << 10) +#define JZ_ADC_REG_CFG_TOUCH_OPS_MASK (BIT(31) | GENMASK(23, 10)) #define JZ_ADC_REG_ADCLK_CLKDIV_LSB 0 #define JZ4725B_ADC_REG_ADCLK_CLKDIV10US_LSB 16 #define JZ4770_ADC_REG_ADCLK_CLKDIV10US_LSB 8 @@ -44,6 +51,14 @@ #define JZ4770_ADC_BATTERY_VREF 6600 #define JZ4770_ADC_BATTERY_VREF_BITS 12 +#define JZ_ADC_IRQ_AUX BIT(0) +#define JZ_ADC_IRQ_BATTERY BIT(1) +#define JZ_ADC_IRQ_TOUCH BIT(2) +#define JZ_ADC_IRQ_PEN_DOWN BIT(3) +#define JZ_ADC_IRQ_PEN_UP BIT(4) +#define JZ_ADC_IRQ_PEN_DOWN_SLEEP BIT(5) +#define JZ_ADC_IRQ_SLEEP BIT(7) + struct ingenic_adc; struct ingenic_adc_soc_data { @@ -428,6 +443,28 @@ static const struct iio_info ingenic_adc_info = { }; static const struct iio_chan_spec ingenic_channels[] = { + { + .type = IIO_POSITIONRELATIVE, + .indexed = 1, + .channel = INGENIC_ADC_TOUCH_XP, + .scan_index = 0, + .scan_type = { + .sign = 'u', + .realbits = 12, + .storagebits = 16, + }, + }, + { + .type = IIO_POSITIONRELATIVE, + .indexed = 1, + .channel = INGENIC_ADC_TOUCH_YP, + .scan_index = 1, + .scan_type = { + .sign = 'u', + .realbits = 12, + .storagebits = 16, + }, + }, { .extend_name = "aux", .type = IIO_VOLTAGE, @@ -435,6 +472,7 @@ static const struct iio_chan_spec ingenic_channels[] = { BIT(IIO_CHAN_INFO_SCALE), .indexed = 1, .channel = INGENIC_ADC_AUX, + .scan_index = -1, }, { .extend_name = "battery", @@ -445,6 +483,7 @@ static const struct iio_chan_spec ingenic_channels[] = { BIT(IIO_CHAN_INFO_SCALE), .indexed = 1, .channel = INGENIC_ADC_BATTERY, + .scan_index = -1, }, { /* Must always be last in the array. */ .extend_name = "aux2", @@ -453,16 +492,76 @@ static const struct iio_chan_spec ingenic_channels[] = { BIT(IIO_CHAN_INFO_SCALE), .indexed = 1, .channel = INGENIC_ADC_AUX2, + .scan_index = -1, }, }; +static int ingenic_adc_buffer_enable(struct iio_dev *iio_dev) +{ + struct ingenic_adc *adc = iio_priv(iio_dev); + int ret; + + ret = clk_enable(adc->clk); + if (ret) { + dev_err(iio_dev->dev.parent, "Failed to enable clock: %d\n", + ret); + return ret; + } + + /* It takes significant time for the touchscreen hw to stabilize. */ + msleep(50); + ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK, + JZ_ADC_REG_CFG_SAMPLE_NUM(4) | + JZ_ADC_REG_CFG_PULL_UP(4)); + writew(80, adc->base + JZ_ADC_REG_ADWAIT); + writew(2, adc->base + JZ_ADC_REG_ADSAME); + writeb((u8)~JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_CTRL); + writel(0, adc->base + JZ_ADC_REG_ADTCH); + ingenic_adc_enable(adc, 2, true); + + return 0; +} + +static int ingenic_adc_buffer_disable(struct iio_dev *iio_dev) +{ + struct ingenic_adc *adc = iio_priv(iio_dev); + + ingenic_adc_enable(adc, 2, false); + writeb(0xff, adc->base + JZ_ADC_REG_CTRL); + writeb(0xff, adc->base + JZ_ADC_REG_STATUS); + ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK, 0); + writew(0, adc->base + JZ_ADC_REG_ADSAME); + writew(0, adc->base + JZ_ADC_REG_ADWAIT); + clk_disable(adc->clk); + + return 0; +} + +static const struct iio_buffer_setup_ops ingenic_buffer_setup_ops = { + .postenable = &ingenic_adc_buffer_enable, + .predisable = &ingenic_adc_buffer_disable +}; + +static irqreturn_t ingenic_adc_irq(int irq, void *data) +{ + struct iio_dev *iio_dev = data; + struct ingenic_adc *adc = iio_priv(iio_dev); + u32 tdat; + + tdat = readl(adc->base + JZ_ADC_REG_ADTCH); + iio_push_to_buffers(iio_dev, &tdat); + writeb(JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_STATUS); + + return IRQ_HANDLED; +} + static int ingenic_adc_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct iio_dev *iio_dev; struct ingenic_adc *adc; const struct ingenic_adc_soc_data *soc_data; - int ret; + int irq, ret; soc_data = device_get_match_data(dev); if (!soc_data) @@ -477,6 +576,17 @@ static int ingenic_adc_probe(struct platform_device *pdev) mutex_init(&adc->aux_lock); adc->soc_data = soc_data; + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + ret = devm_request_irq(dev, irq, ingenic_adc_irq, 0, + dev_name(dev), iio_dev); + if (ret < 0) { + dev_err(dev, "Failed to request irq: %d\n", ret); + return ret; + } + adc->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(adc->base)) return PTR_ERR(adc->base); @@ -516,7 +626,8 @@ static int ingenic_adc_probe(struct platform_device *pdev) iio_dev->dev.parent = dev; iio_dev->name = "jz-adc"; - iio_dev->modes = INDIO_DIRECT_MODE; + iio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE; + iio_dev->setup_ops = &ingenic_buffer_setup_ops; iio_dev->channels = ingenic_channels; iio_dev->num_channels = ARRAY_SIZE(ingenic_channels); /* Remove AUX2 from the list of supported channels. */