lkml.org 
[lkml]   [2020]   [Mar]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 3/5] IIO: Ingenic JZ47xx: Add touchscreen mode.
Hi Jonathan,


Le sam., mars 7, 2020 at 12:47, Jonathan Cameron
<jic23@jic23.retrosnub.co.uk> a écrit :
> On Sun, 1 Mar 2020 16:09:18 +0100
> Artur Rojek <contact@artur-rojek.eu> wrote:
>
>> 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.
>>
>> Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
>> Tested-by: Paul Cercueil <paul@crapouillou.net>
>
> This relies on the use of an irq that wasn't previously used. Was
> that
> always hooked up? If not we need to still work as before when it
> isn't provided.
>
> Otherwise this looks fine to me.

All the boards that probe the ingenic-adc driver have the interrupt
provided from devicetree, yes.

Cheers,
-Paul

>
>> ---
>>
>> 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
>>
>> drivers/iio/adc/Kconfig | 1 +
>> drivers/iio/adc/ingenic-adc.c | 109
>> +++++++++++++++++++++++++++++++++-
>> 2 files changed, 108 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
>> index 82e33082958c..d3fd4b6e2d47 100644
>> --- a/drivers/iio/adc/Kconfig
>> +++ b/drivers/iio/adc/Kconfig
>> @@ -453,6 +453,7 @@ 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 7a24bc1dabe1..0dafc8d5d0d8 100644
>> --- a/drivers/iio/adc/ingenic-adc.c
>> +++ b/drivers/iio/adc/ingenic-adc.c
>> @@ -8,7 +8,9 @@
>>
>> #include <dt-bindings/iio/adc/ingenic,adc.h>
>> #include <linux/clk.h>
>> +#include <linux/iio/buffer.h>
>> #include <linux/iio/iio.h>
>> +#include <linux/interrupt.h>
>> #include <linux/io.h>
>> #include <linux/iopoll.h>
>> #include <linux/kernel.h>
>> @@ -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 {
>> @@ -411,6 +426,28 @@ 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,
>> @@ -418,6 +455,7 @@ 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",
>> @@ -428,6 +466,7 @@ 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",
>> @@ -436,16 +475,69 @@ 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);
>> +
>> + clk_enable(adc->clk);
>> + /* 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)
>> @@ -460,6 +552,18 @@ 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);
>
> Do we need a fallback path if there is no irq provided? We can't
> break existing
> supported devices that don't specify one.
>
>> + if (irq < 0) {
>> + dev_err(dev, "Failed to get irq: %d\n", irq);
>> + 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);
>> @@ -499,7 +603,8 @@ 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. */
>


\
 
 \ /
  Last update: 2020-03-07 14:00    [W:0.111 / U:0.160 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site