[PATCH 5/5] iio: at91: introduce touch screen support in iio adc driver
Mark Rutland
mark.rutland at arm.com
Mon Jul 22 09:17:47 EDT 2013
On Sun, Jul 14, 2013 at 09:04:29AM +0100, 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:
> which type of touch are used? (4 or 5 wires), sample period time,
> pen detect debounce time, average samples and pen detect resistor.
>
> 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>
> ---
> .../devicetree/bindings/arm/atmel-adc.txt | 13 +
> arch/arm/mach-at91/include/mach/at91_adc.h | 34 ++
> drivers/iio/adc/at91_adc.c | 389 ++++++++++++++++++--
> 3 files changed, 412 insertions(+), 24 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/arm/atmel-adc.txt b/Documentation/devicetree/bindings/arm/atmel-adc.txt
> index 0db2945..925d656 100644
> --- a/Documentation/devicetree/bindings/arm/atmel-adc.txt
> +++ b/Documentation/devicetree/bindings/arm/atmel-adc.txt
> @@ -29,6 +29,19 @@ Optional properties:
> - atmel,adc-sample-hold-time: Sample and Hold Time in microseconds
> - atmel,adc-clock-rate: ADC clock rate. If not specified, use the default
> adc_op_clk.
> + - atmel,adc-touchscreen-wires: Number of touch screen wires. Only support
> + 4 and 5 wires touch screen.
Are 4 and 5 wire configurations that can exist, or the only ones
supported by the driver?
> + NOTE: when adc touch screen enabled, the adc hardware trigger will be
> + disabled. Since touch screen will occupied the trigger register.
> + - atmel,adc-ts-pendet-debounce: Debounce time in microsecond for touch pen
> + detect.
For consistency with the adc-touchscreen-wires property, and other
properties with timing information, how about
atmel,adc-touchscreen-debounce-delay-us ?
> + - atmel,adc-ts-sample-period-time: Sample Period Time in microsecond for
> + touch screen
Again, please be consistent with ts or touchscreen. It may also be good
to have -us to make the units explicit (though it does leave the
property name being quite a mothful):
atmel,adc-touchscreen-sample-period-us ?
> + - atmel,adc-ts-filter-average: Numbers of sampling data will be averaged.
> + 0 means no average. 1 means average two samples. 2 means average four
> + samples. 3 means average eight samples.
Is this averaging done in the hardware, or the kernel driver?
If it's the latter, this can be left for the kernel to decide.
> + - atmel,adc-ts-pendet-sensitivity: Pen Detection input pull-up resistor.
> + It can be 0, 1, 2, 3.
I think "pendet" is a bit opaque. "pen-detect" may be better. What
physical property does this represent (are these discrete values, or an
enumeration)?
Thanks,
Mark.
>
> 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 ab273ee..6d6cc14 100644
> --- a/arch/arm/mach-at91/include/mach/at91_adc.h
> +++ b/arch/arm/mach-at91/include/mach/at91_adc.h
> @@ -57,10 +57,44 @@
> #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_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_VERSION 0xFC
>
> +/* 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 8f1386f..ffc0e42 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>
> @@ -39,12 +40,24 @@
> #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 ZTHRESHOLD 9000
> +
> struct at91_adc_caps {
> + bool has_12bits_xy; /* true means use 12 bits. Otherwise 10 bits */
> bool has_tsmr; /* only at91sam9x5, sama5d3 have TSMR reg */
> u32 mr_prescal_mask;
> u32 mr_startup_mask;
> };
>
> +enum atmel_adc_ts_type {
> + ATMEL_ADC_TOUCHSCREEN_NONE = 0,
> + ATMEL_ADC_TOUCHSCREEN_4WIRE,
> + ATMEL_ADC_TOUCHSCREEN_5WIRE,
> +};
> +
> struct at91_adc_state {
> struct clk *adc_clk;
> u32 adc_clk_rate;
> @@ -70,6 +83,29 @@ 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;
> +
> + u8 ts_filter_average;
> + u16 ts_pen_detect_debounce;
> + u8 ts_pen_detect_sensitivity;
> + u16 ts_sample_period_time;
> + u16 ts_sample_period_val;
> };
>
> static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
> @@ -104,14 +140,10 @@ 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);
> @@ -121,6 +153,115 @@ 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->caps.has_12bits_xy ? 12 : 10;
> + 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)
> + x /= xscale;
> + else
> + dev_err(&idev->dev, "xscale == 0!!!\n");
> +
> + /* 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)
> + y /= yscale;
> + else
> + dev_err(&idev->dev, "yscale == 0!!!\n");
> +
> + /* 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 = ZTHRESHOLD; /* 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 < ZTHRESHOLD) {
> + 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;
> }
> @@ -130,6 +271,16 @@ 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;
> @@ -561,6 +712,57 @@ static int at91_adc_probe_dt(struct at91_adc_state *st,
> i++;
> }
>
> + /* Check if touchscreen is enabled in DT. */
> + ret = of_property_read_u32(node, "atmel,adc-touchscreen-wires", &prop);
> + if (ret)
> + dev_info(&idev->dev, "Touchscreen not enabled.\n");
> + else if (prop == 4)
> + st->touchscreen_type = ATMEL_ADC_TOUCHSCREEN_4WIRE;
> + else if (prop == 5)
> + st->touchscreen_type = ATMEL_ADC_TOUCHSCREEN_5WIRE;
> + else
> + dev_warn(&idev->dev, "Unsupported number of touchscreen wires (%d)\n",
> + prop);
> +
> + if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_NONE)
> + return 0;
> +
> + /* Touch screen is enabled, so check touch screen dt parameters */
> + if (of_property_read_u32(node, "atmel,adc-ts-filter-average", &prop)) {
> + dev_err(&idev->dev, "Missing atmel,adc-ts-filtering-average property in the DT.\n");
> + ret = -EINVAL;
> + goto error_ret;
> + }
> + st->ts_filter_average = prop;
> + if (st->ts_filter_average > 3) {
> + dev_err(&idev->dev, "Invalid atmel,adc-ts-filtering-average property in the DT.\n");
> + ret = -EINVAL;
> + goto error_ret;
> + }
> +
> + prop = 0;
> + of_property_read_u32(node, "atmel,adc-ts-pendet-debounce", &prop);
> + st->ts_pen_detect_debounce = prop;
> +
> + /* default sample period is 2ms. The real touch sample period should be
> + * this period * TSFREQ.
> + */
> + prop = 2000;
> + of_property_read_u32(node, "atmel,adc-ts-sample-period-time", &prop);
> + st->ts_sample_period_time = prop;
> +
> + if (of_property_read_u32(node, "atmel,adc-ts-pendet-sensitivity", &prop)) {
> + dev_err(&idev->dev, "Missing atmel,adc-ts-pendet-sensitivity property in the DT.\n");
> + ret = -EINVAL;
> + goto error_ret;
> + }
> + st->ts_pen_detect_sensitivity = prop;
> + if (st->ts_pen_detect_sensitivity > 3) {
> + dev_err(&idev->dev, "Invalid atmel,adc-ts-pendet-sensitivity property in the DT.\n");
> + ret = -EINVAL;
> + goto error_ret;
> + }
> +
> return 0;
>
> error_ret:
> @@ -592,6 +794,114 @@ 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(st->ts_pen_detect_debounce * 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->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->ts_pen_detect_sensitivity
> + & AT91_ADC_ACR_PENDETSENS);
> +
> + /* Sample Peroid Time = (TRGPER + 1) / ADCClock */
> + st->ts_sample_period_val = round_up((st->ts_sample_period_time *
> + adc_clk_khz / 1000) - 1, 1);
> +
> + return 0;
> +}
> +
> +static int at91_ts_register(struct at91_adc_state *st)
> +{
> + 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 = idev->dev.parent;
> + 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);
> + input_free_device(st->ts_input);
> +}
> +
> /*
> * Since atmel adc support different ip for touchscreen mode. Through the
> * IP check, we will know the touchscreen capbilities.
> @@ -610,6 +920,7 @@ static void atmel_adc_get_cap(struct at91_adc_state *st)
> /* keep only major version number */
> switch (version & 0xf00) {
> case 0x500: /* SAMA5D3 */
> + st->caps.has_12bits_xy = 1;
> case 0x400: /* AT91SAM9X5/9N12 */
> st->caps.has_tsmr = 1;
> st->caps.mr_startup_mask = AT91_ADC_STARTUP;
> @@ -683,7 +994,7 @@ 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);
> @@ -731,6 +1042,10 @@ static int at91_adc_probe(struct platform_device *pdev)
> adc_clk = st->adc_clk_rate ?
> st->adc_clk_rate : 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) {
> @@ -799,30 +1114,52 @@ 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);
> + 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:
> @@ -841,8 +1178,12 @@ 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);
> @@ -861,7 +1202,7 @@ 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),
> },
> };
> --
> 1.7.10
>
>
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