[PATCH 3/3] iio: at91: introduce touch screen support in iio adc driver
Josh Wu
josh.wu at atmel.com
Thu Oct 17 01:20:52 EDT 2013
Hi, Dimitry
Could give some feedback for this v4 patch if you have time? Since It
has been stuck for a while.
Thanks.
Best Regards,
Josh Wu
On 10/10/2013 4:14 AM, Jonathan Cameron wrote:
> On 10/08/13 04:48, Josh Wu wrote:
>> AT91 ADC hardware integrate touch screen support. So this patch add touch
>> screen support for at91 adc iio driver.
>> To enable touch screen support in adc, you need to add the dt parameters:
>> 1. which type of touch are used? (4 or 5 wires), sample period time.
>> 2. correct pressure detect threshold value.
>>
>> In the meantime, since touch screen will use a interal period trigger of adc,
>> so it is conflict to other hardware triggers. Driver will disable the hardware
>> trigger support if touch screen is enabled.
>>
>> This driver has been tested in AT91SAM9X5-EK and SAMA5D3x-EK.
>>
>> Signed-off-by: Josh Wu <josh.wu at atmel.com>
>> Cc: Dmitry Torokhov <dmitry.torokhov at gmail.com>
>> CC: devicetree at vger.kernel.org
> Hi Josh. I am not going to take this for now both because I want to have
> a close read of it when I have more time and because I want input from
> Dmitry on this one.
>
> Thanks,
>
> Jonathan
>> ---
>> .../devicetree/bindings/arm/atmel-adc.txt | 7 +
>> arch/arm/mach-at91/include/mach/at91_adc.h | 34 ++
>> drivers/iio/adc/at91_adc.c | 388 ++++++++++++++++++--
>> 3 files changed, 405 insertions(+), 24 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/arm/atmel-adc.txt b/Documentation/devicetree/bindings/arm/atmel-adc.txt
>> index 0e65e01..d106146 100644
>> --- a/Documentation/devicetree/bindings/arm/atmel-adc.txt
>> +++ b/Documentation/devicetree/bindings/arm/atmel-adc.txt
>> @@ -23,6 +23,13 @@ Optional properties:
>> resolution will be used.
>> - atmel,adc-sleep-mode: Boolean to enable sleep mode when no conversion
>> - atmel,adc-sample-hold-time: Sample and Hold Time in microseconds
>> + - atmel,adc-ts-wires: Number of touch screen wires. Should be 4 or 5. If this
>> + value is set, then adc driver will enable touch screen
>> + support.
>> + NOTE: when adc touch screen enabled, the adc hardware trigger will be
>> + disabled. Since touch screen will occupied the trigger register.
>> + - atmel,adc-ts-pressure-threshold: a pressure threshold for touchscreen. It
>> + make touch detect more precision.
>>
>> Optional trigger Nodes:
>> - Required properties:
>> diff --git a/arch/arm/mach-at91/include/mach/at91_adc.h b/arch/arm/mach-at91/include/mach/at91_adc.h
>> index 048a57f..c287307 100644
>> --- a/arch/arm/mach-at91/include/mach/at91_adc.h
>> +++ b/arch/arm/mach-at91/include/mach/at91_adc.h
>> @@ -60,14 +60,48 @@
>> #define AT91_ADC_IER 0x24 /* Interrupt Enable Register */
>> #define AT91_ADC_IDR 0x28 /* Interrupt Disable Register */
>> #define AT91_ADC_IMR 0x2C /* Interrupt Mask Register */
>> +#define AT91_ADC_IER_PEN (1 << 29)
>> +#define AT91_ADC_IER_NOPEN (1 << 30)
>> +#define AT91_ADC_IER_XRDY (1 << 20)
>> +#define AT91_ADC_IER_YRDY (1 << 21)
>> +#define AT91_ADC_IER_PRDY (1 << 22)
>> +#define AT91_ADC_ISR_PENS (1 << 31)
>>
>> #define AT91_ADC_CHR(n) (0x30 + ((n) * 4)) /* Channel Data Register N */
>> #define AT91_ADC_DATA (0x3ff)
>>
>> #define AT91_ADC_CDR0_9X5 (0x50) /* Channel Data Register 0 for 9X5 */
>>
>> +#define AT91_ADC_ACR 0x94 /* Analog Control Register */
>> +#define AT91_ADC_ACR_PENDETSENS (0x3 << 0) /* pull-up resistor */
>> +
>> +#define AT91_ADC_TSMR 0xB0
>> +#define AT91_ADC_TSMR_TSMODE (3 << 0) /* Touch Screen Mode */
>> +#define AT91_ADC_TSMR_TSMODE_NONE (0 << 0)
>> +#define AT91_ADC_TSMR_TSMODE_4WIRE_NO_PRESS (1 << 0)
>> +#define AT91_ADC_TSMR_TSMODE_4WIRE_PRESS (2 << 0)
>> +#define AT91_ADC_TSMR_TSMODE_5WIRE (3 << 0)
>> +#define AT91_ADC_TSMR_TSAV (3 << 4) /* Averages samples */
>> +#define AT91_ADC_TSMR_TSAV_(x) ((x) << 4)
>> +#define AT91_ADC_TSMR_SCTIM (0x0f << 16) /* Switch closure time */
>> +#define AT91_ADC_TSMR_PENDBC (0x0f << 28) /* Pen Debounce time */
>> +#define AT91_ADC_TSMR_PENDBC_(x) ((x) << 28)
>> +#define AT91_ADC_TSMR_NOTSDMA (1 << 22) /* No Touchscreen DMA */
>> +#define AT91_ADC_TSMR_PENDET_DIS (0 << 24) /* Pen contact detection disable */
>> +#define AT91_ADC_TSMR_PENDET_ENA (1 << 24) /* Pen contact detection enable */
>> +
>> +#define AT91_ADC_TSXPOSR 0xB4
>> +#define AT91_ADC_TSYPOSR 0xB8
>> +#define AT91_ADC_TSPRESSR 0xBC
>> +
>> #define AT91_ADC_TRGR_9260 AT91_ADC_MR
>> #define AT91_ADC_TRGR_9G45 0x08
>> #define AT91_ADC_TRGR_9X5 0xC0
>>
>> +/* Trigger Register bit field */
>> +#define AT91_ADC_TRGR_TRGPER (0xffff << 16)
>> +#define AT91_ADC_TRGR_TRGPER_(x) ((x) << 16)
>> +#define AT91_ADC_TRGR_TRGMOD (0x7 << 0)
>> +#define AT91_ADC_TRGR_MOD_PERIOD_TRIG (5 << 0)
>> +
>> #endif
>> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
>> index 22cf61d2..68ddd7f 100644
>> --- a/drivers/iio/adc/at91_adc.c
>> +++ b/drivers/iio/adc/at91_adc.c
>> @@ -11,6 +11,7 @@
>> #include <linux/clk.h>
>> #include <linux/err.h>
>> #include <linux/io.h>
>> +#include <linux/input.h>
>> #include <linux/interrupt.h>
>> #include <linux/jiffies.h>
>> #include <linux/kernel.h>
>> @@ -39,7 +40,23 @@
>> #define at91_adc_writel(st, reg, val) \
>> (writel_relaxed(val, st->reg_base + reg))
>>
>> +#define DRIVER_NAME "at91_adc"
>> +#define MAX_POS_BITS 12
>> +
>> +#define TOUCH_SAMPLE_PERIOD_US 2000 /* 2ms */
>> +#define TOUCH_PEN_DETECT_DEBOUNCE_US 200
>> +
>> struct at91_adc_caps {
>> + bool has_ts; /* Support touch screen */
>> + bool has_tsmr; /* only at91sam9x5, sama5d3 have TSMR reg */
>> + /*
>> + * Numbers of sampling data will be averaged. Can be 0~3.
>> + * Hardware can average (2 ^ ts_filter_average) sample data.
>> + */
>> + u8 ts_filter_average;
>> + /* Pen Detection input pull-up resistor, can be 0~3 */
>> + u8 ts_pen_detect_sensitivity;
>> +
>> /* startup time calculate function */
>> u32 (*calc_startup_ticks)(u8 startup_time, u32 adc_clk_khz);
>>
>> @@ -47,6 +64,12 @@ struct at91_adc_caps {
>> struct at91_adc_reg_desc registers;
>> };
>>
>> +enum atmel_adc_ts_type {
>> + ATMEL_ADC_TOUCHSCREEN_NONE = 0,
>> + ATMEL_ADC_TOUCHSCREEN_4WIRE = 4,
>> + ATMEL_ADC_TOUCHSCREEN_5WIRE = 5,
>> +};
>> +
>> struct at91_adc_state {
>> struct clk *adc_clk;
>> u16 *buffer;
>> @@ -71,6 +94,26 @@ struct at91_adc_state {
>> bool low_res; /* the resolution corresponds to the lowest one */
>> wait_queue_head_t wq_data_avail;
>> struct at91_adc_caps *caps;
>> +
>> + /*
>> + * Following ADC channels are shared by touchscreen:
>> + *
>> + * CH0 -- Touch screen XP/UL
>> + * CH1 -- Touch screen XM/UR
>> + * CH2 -- Touch screen YP/LL
>> + * CH3 -- Touch screen YM/Sense
>> + * CH4 -- Touch screen LR(5-wire only)
>> + *
>> + * The bitfields below represents the reserved channel in the
>> + * touchscreen mode.
>> + */
>> +#define CHAN_MASK_TOUCHSCREEN_4WIRE (0xf << 0)
>> +#define CHAN_MASK_TOUCHSCREEN_5WIRE (0x1f << 0)
>> + enum atmel_adc_ts_type touchscreen_type;
>> + struct input_dev *ts_input;
>> +
>> + u16 ts_sample_period_val;
>> + u32 ts_pressure_threshold;
>> };
>>
>> static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
>> @@ -105,14 +148,10 @@ static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
>> return IRQ_HANDLED;
>> }
>>
>> -static irqreturn_t at91_adc_eoc_trigger(int irq, void *private)
>> +/* Handler for classic adc channel eoc trigger */
>> +void handle_adc_eoc_trigger(int irq, struct iio_dev *idev)
>> {
>> - struct iio_dev *idev = private;
>> struct at91_adc_state *st = iio_priv(idev);
>> - u32 status = at91_adc_readl(st, st->registers->status_register);
>> -
>> - if (!(status & st->registers->drdy_mask))
>> - return IRQ_HANDLED;
>>
>> if (iio_buffer_enabled(idev)) {
>> disable_irq_nosync(irq);
>> @@ -122,6 +161,115 @@ static irqreturn_t at91_adc_eoc_trigger(int irq, void *private)
>> st->done = true;
>> wake_up_interruptible(&st->wq_data_avail);
>> }
>> +}
>> +
>> +static int at91_ts_sample(struct at91_adc_state *st)
>> +{
>> + unsigned int xscale, yscale, reg, z1, z2;
>> + unsigned int x, y, pres, xpos, ypos;
>> + unsigned int rxp = 1;
>> + unsigned int factor = 1000;
>> + struct iio_dev *idev = iio_priv_to_dev(st);
>> +
>> + unsigned int xyz_mask_bits = st->res;
>> + unsigned int xyz_mask = (1 << xyz_mask_bits) - 1;
>> +
>> + /* calculate position */
>> + /* x position = (x / xscale) * max, max = 2^MAX_POS_BITS - 1 */
>> + reg = at91_adc_readl(st, AT91_ADC_TSXPOSR);
>> + xpos = reg & xyz_mask;
>> + x = (xpos << MAX_POS_BITS) - xpos;
>> + xscale = (reg >> 16) & xyz_mask;
>> + if (xscale == 0) {
>> + dev_err(&idev->dev, "Error: xscale == 0!\n");
>> + return -1;
>> + }
>> + x /= xscale;
>> +
>> + /* y position = (y / yscale) * max, max = 2^MAX_POS_BITS - 1 */
>> + reg = at91_adc_readl(st, AT91_ADC_TSYPOSR);
>> + ypos = reg & xyz_mask;
>> + y = (ypos << MAX_POS_BITS) - ypos;
>> + yscale = (reg >> 16) & xyz_mask;
>> + if (yscale == 0) {
>> + dev_err(&idev->dev, "Error: yscale == 0!\n");
>> + return -1;
>> + }
>> + y /= yscale;
>> +
>> + /* calculate the pressure */
>> + reg = at91_adc_readl(st, AT91_ADC_TSPRESSR);
>> + z1 = reg & xyz_mask;
>> + z2 = (reg >> 16) & xyz_mask;
>> +
>> + if (z1 != 0)
>> + pres = rxp * (x * factor / 1024) * (z2 * factor / z1 - factor)
>> + / factor;
>> + else
>> + pres = st->ts_pressure_threshold; /* no pen contacted */
>> +
>> + dev_dbg(&idev->dev, "xpos = %d, xscale = %d, ypos = %d, yscale = %d, z1 = %d, z2 = %d, press = %d\n",
>> + xpos, xscale, ypos, yscale, z1, z2, pres);
>> +
>> + if (pres < st->ts_pressure_threshold) {
>> + dev_dbg(&idev->dev, "x = %d, y = %d, pressure = %d\n",
>> + x, y, pres / factor);
>> + input_report_abs(st->ts_input, ABS_X, x);
>> + input_report_abs(st->ts_input, ABS_Y, y);
>> + input_report_abs(st->ts_input, ABS_PRESSURE, pres);
>> + input_report_key(st->ts_input, BTN_TOUCH, 1);
>> + input_sync(st->ts_input);
>> + } else {
>> + dev_dbg(&idev->dev, "pressure too low: not reporting\n");
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static irqreturn_t at91_adc_interrupt(int irq, void *private)
>> +{
>> + struct iio_dev *idev = private;
>> + struct at91_adc_state *st = iio_priv(idev);
>> + u32 status = at91_adc_readl(st, st->registers->status_register);
>> + const uint32_t ts_data_irq_mask =
>> + AT91_ADC_IER_XRDY |
>> + AT91_ADC_IER_YRDY |
>> + AT91_ADC_IER_PRDY;
>> +
>> + if (status & st->registers->drdy_mask)
>> + handle_adc_eoc_trigger(irq, idev);
>> +
>> + if (status & AT91_ADC_IER_PEN) {
>> + at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);
>> + at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_NOPEN |
>> + ts_data_irq_mask);
>> + /* Set up period trigger for sampling */
>> + at91_adc_writel(st, st->registers->trigger_register,
>> + AT91_ADC_TRGR_MOD_PERIOD_TRIG |
>> + AT91_ADC_TRGR_TRGPER_(st->ts_sample_period_val));
>> + } else if (status & AT91_ADC_IER_NOPEN) {
>> + at91_adc_writel(st, st->registers->trigger_register, 0);
>> + at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_NOPEN |
>> + ts_data_irq_mask);
>> + at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);
>> +
>> + input_report_key(st->ts_input, BTN_TOUCH, 0);
>> + input_sync(st->ts_input);
>> + } else if ((status & ts_data_irq_mask) == ts_data_irq_mask) {
>> + /* Now all touchscreen data is ready */
>> +
>> + if (status & AT91_ADC_ISR_PENS) {
>> + /* validate data by pen contact */
>> + at91_ts_sample(st);
>> + } else {
>> + /* triggered by event that is no pen contact, just read
>> + * them to clean the interrupt and discard all.
>> + */
>> + at91_adc_readl(st, AT91_ADC_TSXPOSR);
>> + at91_adc_readl(st, AT91_ADC_TSYPOSR);
>> + at91_adc_readl(st, AT91_ADC_TSPRESSR);
>> + }
>> + }
>>
>> return IRQ_HANDLED;
>> }
>> @@ -131,6 +279,16 @@ static int at91_adc_channel_init(struct iio_dev *idev)
>> struct at91_adc_state *st = iio_priv(idev);
>> struct iio_chan_spec *chan_array, *timestamp;
>> int bit, idx = 0;
>> + unsigned long rsvd_mask = 0;
>> +
>> + /* If touchscreen is enable, then reserve the adc channels */
>> + if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE)
>> + rsvd_mask = CHAN_MASK_TOUCHSCREEN_4WIRE;
>> + else if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_5WIRE)
>> + rsvd_mask = CHAN_MASK_TOUCHSCREEN_5WIRE;
>> +
>> + /* set up the channel mask to reserve touchscreen channels */
>> + st->channels_mask &= ~rsvd_mask;
>>
>> idev->num_channels = bitmap_weight(&st->channels_mask,
>> st->num_channels) + 1;
>> @@ -479,6 +637,39 @@ static u32 calc_startup_ticks_9x5(u8 startup_time, u32 adc_clk_khz)
>>
>> static const struct of_device_id at91_adc_dt_ids[];
>>
>> +static int at91_adc_probe_dt_ts(struct device_node *node,
>> + struct at91_adc_state *st, struct device *dev)
>> +{
>> + int ret;
>> + u32 prop;
>> +
>> + ret = of_property_read_u32(node, "atmel,adc-ts-wires", &prop);
>> + if (ret) {
>> + dev_info(dev, "ADC Touch screen is disabled.\n");
>> + return 0;
>> + }
>> +
>> + switch (prop) {
>> + case 4:
>> + case 5:
>> + st->touchscreen_type = prop;
>> + break;
>> + default:
>> + dev_err(dev, "Unsupported number of touchscreen wires (%d). Should be 4 or 5.\n", prop);
>> + return -EINVAL;
>> + }
>> +
>> + prop = 0;
>> + of_property_read_u32(node, "atmel,adc-ts-pressure-threshold", &prop);
>> + st->ts_pressure_threshold = prop;
>> + if (st->ts_pressure_threshold) {
>> + return 0;
>> + } else {
>> + dev_err(dev, "Invalid pressure threshold for the touchscreen\n");
>> + return -EINVAL;
>> + }
>> +}
>> +
>> static int at91_adc_probe_dt(struct at91_adc_state *st,
>> struct platform_device *pdev)
>> {
>> @@ -560,6 +751,12 @@ static int at91_adc_probe_dt(struct at91_adc_state *st,
>> i++;
>> }
>>
>> + /* Check if touchscreen is supported. */
>> + if (st->caps->has_ts)
>> + return at91_adc_probe_dt_ts(node, st, &idev->dev);
>> + else
>> + dev_info(&idev->dev, "not support touchscreen in the adc compatible string.\n");
>> +
>> return 0;
>>
>> error_ret:
>> @@ -591,6 +788,114 @@ static const struct iio_info at91_adc_info = {
>> .read_raw = &at91_adc_read_raw,
>> };
>>
>> +/* Touchscreen related functions */
>> +static int atmel_ts_open(struct input_dev *dev)
>> +{
>> + struct at91_adc_state *st = input_get_drvdata(dev);
>> +
>> + at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);
>> + return 0;
>> +}
>> +
>> +static void atmel_ts_close(struct input_dev *dev)
>> +{
>> + struct at91_adc_state *st = input_get_drvdata(dev);
>> +
>> + at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);
>> +}
>> +
>> +static int at91_ts_hw_init(struct at91_adc_state *st, u32 adc_clk_khz)
>> +{
>> + u32 reg = 0, pendbc;
>> + int i = 0;
>> +
>> + if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE)
>> + reg = AT91_ADC_TSMR_TSMODE_4WIRE_PRESS;
>> + else
>> + reg = AT91_ADC_TSMR_TSMODE_5WIRE;
>> +
>> + /* a Pen Detect Debounce Time is necessary for the ADC Touch to avoid
>> + * pen detect noise.
>> + * The formula is : Pen Detect Debounce Time = (2 ^ pendbc) / ADCClock
>> + */
>> + pendbc = round_up(TOUCH_PEN_DETECT_DEBOUNCE_US * adc_clk_khz / 1000, 1);
>> +
>> + while (pendbc >> ++i)
>> + ; /* Empty! Find the shift offset */
>> + if (abs(pendbc - (1 << i)) < abs(pendbc - (1 << (i - 1))))
>> + pendbc = i;
>> + else
>> + pendbc = i - 1;
>> +
>> + if (st->caps->has_tsmr) {
>> + reg |= AT91_ADC_TSMR_TSAV_(st->caps->ts_filter_average)
>> + & AT91_ADC_TSMR_TSAV;
>> + reg |= AT91_ADC_TSMR_PENDBC_(pendbc) & AT91_ADC_TSMR_PENDBC;
>> + reg |= AT91_ADC_TSMR_NOTSDMA;
>> + reg |= AT91_ADC_TSMR_PENDET_ENA;
>> + reg |= 0x03 << 8; /* TSFREQ, need bigger than TSAV */
>> +
>> + at91_adc_writel(st, AT91_ADC_TSMR, reg);
>> + } else {
>> + /* TODO: for 9g45 which has no TSMR */
>> + }
>> +
>> + /* Change adc internal resistor value for better pen detection,
>> + * default value is 100 kOhm.
>> + * 0 = 200 kOhm, 1 = 150 kOhm, 2 = 100 kOhm, 3 = 50 kOhm
>> + * option only available on ES2 and higher
>> + */
>> + at91_adc_writel(st, AT91_ADC_ACR, st->caps->ts_pen_detect_sensitivity
>> + & AT91_ADC_ACR_PENDETSENS);
>> +
>> + /* Sample Peroid Time = (TRGPER + 1) / ADCClock */
>> + st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US *
>> + adc_clk_khz / 1000) - 1, 1);
>> +
>> + return 0;
>> +}
>> +
>> +static int at91_ts_register(struct at91_adc_state *st,
>> + struct platform_device *pdev)
>> +{
>> + struct input_dev *input;
>> + struct iio_dev *idev = iio_priv_to_dev(st);
>> + int ret;
>> +
>> + input = input_allocate_device();
>> + if (!input) {
>> + dev_err(&idev->dev, "Failed to allocate TS device!\n");
>> + return -ENOMEM;
>> + }
>> +
>> + input->name = DRIVER_NAME;
>> + input->id.bustype = BUS_HOST;
>> + input->dev.parent = &pdev->dev;
>> + input->open = atmel_ts_open;
>> + input->close = atmel_ts_close;
>> +
>> + __set_bit(EV_ABS, input->evbit);
>> + __set_bit(EV_KEY, input->evbit);
>> + __set_bit(BTN_TOUCH, input->keybit);
>> + input_set_abs_params(input, ABS_X, 0, (1 << MAX_POS_BITS) - 1, 0, 0);
>> + input_set_abs_params(input, ABS_Y, 0, (1 << MAX_POS_BITS) - 1, 0, 0);
>> + input_set_abs_params(input, ABS_PRESSURE, 0, 0xffffff, 0, 0);
>> +
>> + st->ts_input = input;
>> + input_set_drvdata(input, st);
>> +
>> + ret = input_register_device(input);
>> + if (ret)
>> + input_free_device(st->ts_input);
>> +
>> + return ret;
>> +}
>> +
>> +static void at91_ts_unregister(struct at91_adc_state *st)
>> +{
>> + input_unregister_device(st->ts_input);
>> +}
>> +
>> static int at91_adc_probe(struct platform_device *pdev)
>> {
>> unsigned int prsc, mstrclk, ticks, adc_clk, adc_clk_khz, shtim;
>> @@ -642,7 +947,7 @@ static int at91_adc_probe(struct platform_device *pdev)
>> at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST);
>> at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);
>> ret = request_irq(st->irq,
>> - at91_adc_eoc_trigger,
>> + at91_adc_interrupt,
>> 0,
>> pdev->dev.driver->name,
>> idev);
>> @@ -687,6 +992,10 @@ static int at91_adc_probe(struct platform_device *pdev)
>> mstrclk = clk_get_rate(st->clk);
>> adc_clk = clk_get_rate(st->adc_clk);
>> adc_clk_khz = adc_clk / 1000;
>> +
>> + dev_dbg(&pdev->dev, "Master clock is set as: %d Hz, adc_clk should set as: %d Hz\n",
>> + mstrclk, adc_clk);
>> +
>> prsc = (mstrclk / (2 * adc_clk)) - 1;
>>
>> if (!st->startup_time) {
>> @@ -723,30 +1032,52 @@ static int at91_adc_probe(struct platform_device *pdev)
>> init_waitqueue_head(&st->wq_data_avail);
>> mutex_init(&st->lock);
>>
>> - ret = at91_adc_buffer_init(idev);
>> - if (ret < 0) {
>> - dev_err(&pdev->dev, "Couldn't initialize the buffer.\n");
>> - goto error_disable_adc_clk;
>> - }
>> + /*
>> + * Since touch screen will set trigger register as period trigger. So
>> + * when touch screen is enabled, then we have to disable hardware
>> + * trigger for classic adc.
>> + */
>> + if (!st->touchscreen_type) {
>> + ret = at91_adc_buffer_init(idev);
>> + if (ret < 0) {
>> + dev_err(&pdev->dev, "Couldn't initialize the buffer.\n");
>> + goto error_disable_adc_clk;
>> + }
>>
>> - ret = at91_adc_trigger_init(idev);
>> - if (ret < 0) {
>> - dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
>> - goto error_unregister_buffer;
>> + ret = at91_adc_trigger_init(idev);
>> + if (ret < 0) {
>> + dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
>> + at91_adc_buffer_remove(idev);
>> + goto error_disable_adc_clk;
>> + }
>> + } else {
>> + if (!st->caps->has_tsmr) {
>> + dev_err(&pdev->dev, "We don't support non-TSMR adc\n");
>> + goto error_disable_adc_clk;
>> + }
>> +
>> + ret = at91_ts_register(st, pdev);
>> + if (ret)
>> + goto error_disable_adc_clk;
>> +
>> + at91_ts_hw_init(st, adc_clk_khz);
>> }
>>
>> ret = iio_device_register(idev);
>> if (ret < 0) {
>> dev_err(&pdev->dev, "Couldn't register the device.\n");
>> - goto error_remove_triggers;
>> + goto error_iio_device_register;
>> }
>>
>> return 0;
>>
>> -error_remove_triggers:
>> - at91_adc_trigger_remove(idev);
>> -error_unregister_buffer:
>> - at91_adc_buffer_remove(idev);
>> +error_iio_device_register:
>> + if (!st->touchscreen_type) {
>> + at91_adc_trigger_remove(idev);
>> + at91_adc_buffer_remove(idev);
>> + } else {
>> + at91_ts_unregister(st);
>> + }
>> error_disable_adc_clk:
>> clk_disable_unprepare(st->adc_clk);
>> error_disable_clk:
>> @@ -762,8 +1093,12 @@ static int at91_adc_remove(struct platform_device *pdev)
>> struct at91_adc_state *st = iio_priv(idev);
>>
>> iio_device_unregister(idev);
>> - at91_adc_trigger_remove(idev);
>> - at91_adc_buffer_remove(idev);
>> + if (!st->touchscreen_type) {
>> + at91_adc_trigger_remove(idev);
>> + at91_adc_buffer_remove(idev);
>> + } else {
>> + at91_ts_unregister(st);
>> + }
>> clk_disable_unprepare(st->adc_clk);
>> clk_disable_unprepare(st->clk);
>> free_irq(st->irq, idev);
>> @@ -786,6 +1121,7 @@ static struct at91_adc_caps at91sam9260_caps = {
>> };
>>
>> static struct at91_adc_caps at91sam9g45_caps = {
>> + .has_ts = true,
>> .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */
>> .num_channels = 8,
>> .registers = {
>> @@ -799,6 +1135,10 @@ static struct at91_adc_caps at91sam9g45_caps = {
>> };
>>
>> static struct at91_adc_caps at91sam9x5_caps = {
>> + .has_ts = true,
>> + .has_tsmr = true,
>> + .ts_filter_average = 3,
>> + .ts_pen_detect_sensitivity = 2,
>> .calc_startup_ticks = calc_startup_ticks_9x5,
>> .num_channels = 12,
>> .registers = {
>> @@ -825,7 +1165,7 @@ static struct platform_driver at91_adc_driver = {
>> .probe = at91_adc_probe,
>> .remove = at91_adc_remove,
>> .driver = {
>> - .name = "at91_adc",
>> + .name = DRIVER_NAME,
>> .of_match_table = of_match_ptr(at91_adc_dt_ids),
>> },
>> };
>>
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