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path: root/drivers/iio/adc/at91_adc.c
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Diffstat (limited to 'drivers/iio/adc/at91_adc.c')
-rw-r--r--drivers/iio/adc/at91_adc.c773
1 files changed, 705 insertions, 68 deletions
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index 0f16b553e06..2b6a9ce9927 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>
@@ -30,7 +31,108 @@
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
-#include <mach/at91_adc.h>
+/* Registers */
+#define AT91_ADC_CR 0x00 /* Control Register */
+#define AT91_ADC_SWRST (1 << 0) /* Software Reset */
+#define AT91_ADC_START (1 << 1) /* Start Conversion */
+
+#define AT91_ADC_MR 0x04 /* Mode Register */
+#define AT91_ADC_TSAMOD (3 << 0) /* ADC mode */
+#define AT91_ADC_TSAMOD_ADC_ONLY_MODE (0 << 0) /* ADC Mode */
+#define AT91_ADC_TSAMOD_TS_ONLY_MODE (1 << 0) /* Touch Screen Only Mode */
+#define AT91_ADC_TRGEN (1 << 0) /* Trigger Enable */
+#define AT91_ADC_TRGSEL (7 << 1) /* Trigger Selection */
+#define AT91_ADC_TRGSEL_TC0 (0 << 1)
+#define AT91_ADC_TRGSEL_TC1 (1 << 1)
+#define AT91_ADC_TRGSEL_TC2 (2 << 1)
+#define AT91_ADC_TRGSEL_EXTERNAL (6 << 1)
+#define AT91_ADC_LOWRES (1 << 4) /* Low Resolution */
+#define AT91_ADC_SLEEP (1 << 5) /* Sleep Mode */
+#define AT91_ADC_PENDET (1 << 6) /* Pen contact detection enable */
+#define AT91_ADC_PRESCAL_9260 (0x3f << 8) /* Prescalar Rate Selection */
+#define AT91_ADC_PRESCAL_9G45 (0xff << 8)
+#define AT91_ADC_PRESCAL_(x) ((x) << 8)
+#define AT91_ADC_STARTUP_9260 (0x1f << 16) /* Startup Up Time */
+#define AT91_ADC_STARTUP_9G45 (0x7f << 16)
+#define AT91_ADC_STARTUP_9X5 (0xf << 16)
+#define AT91_ADC_STARTUP_(x) ((x) << 16)
+#define AT91_ADC_SHTIM (0xf << 24) /* Sample & Hold Time */
+#define AT91_ADC_SHTIM_(x) ((x) << 24)
+#define AT91_ADC_PENDBC (0x0f << 28) /* Pen Debounce time */
+#define AT91_ADC_PENDBC_(x) ((x) << 28)
+
+#define AT91_ADC_TSR 0x0C
+#define AT91_ADC_TSR_SHTIM (0xf << 24) /* Sample & Hold Time */
+#define AT91_ADC_TSR_SHTIM_(x) ((x) << 24)
+
+#define AT91_ADC_CHER 0x10 /* Channel Enable Register */
+#define AT91_ADC_CHDR 0x14 /* Channel Disable Register */
+#define AT91_ADC_CHSR 0x18 /* Channel Status Register */
+#define AT91_ADC_CH(n) (1 << (n)) /* Channel Number */
+
+#define AT91_ADC_SR 0x1C /* Status Register */
+#define AT91_ADC_EOC(n) (1 << (n)) /* End of Conversion on Channel N */
+#define AT91_ADC_OVRE(n) (1 << ((n) + 8))/* Overrun Error on Channel N */
+#define AT91_ADC_DRDY (1 << 16) /* Data Ready */
+#define AT91_ADC_GOVRE (1 << 17) /* General Overrun Error */
+#define AT91_ADC_ENDRX (1 << 18) /* End of RX Buffer */
+#define AT91_ADC_RXFUFF (1 << 19) /* RX Buffer Full */
+
+#define AT91_ADC_SR_9X5 0x30 /* Status Register for 9x5 */
+#define AT91_ADC_SR_DRDY_9X5 (1 << 24) /* Data Ready */
+
+#define AT91_ADC_LCDR 0x20 /* Last Converted Data Register */
+#define AT91_ADC_LDATA (0x3ff)
+
+#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 AT91RL_ADC_IER_PEN (1 << 20)
+#define AT91RL_ADC_IER_NOPEN (1 << 21)
+#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_NONE (0 << 0)
+#define AT91_ADC_TRGR_MOD_PERIOD_TRIG (5 << 0)
#define AT91_ADC_CHAN(st, ch) \
(st->registers->channel_base + (ch * 4))
@@ -39,7 +141,50 @@
#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
+
+#define MAX_RLPOS_BITS 10
+#define TOUCH_SAMPLE_PERIOD_US_RL 10000 /* 10ms, the SoC can't keep up with 2ms */
+#define TOUCH_SHTIM 0xa
+
+/**
+ * struct at91_adc_reg_desc - Various informations relative to registers
+ * @channel_base: Base offset for the channel data registers
+ * @drdy_mask: Mask of the DRDY field in the relevant registers
+ (Interruptions registers mostly)
+ * @status_register: Offset of the Interrupt Status Register
+ * @trigger_register: Offset of the Trigger setup register
+ * @mr_prescal_mask: Mask of the PRESCAL field in the adc MR register
+ * @mr_startup_mask: Mask of the STARTUP field in the adc MR register
+ */
+struct at91_adc_reg_desc {
+ u8 channel_base;
+ u32 drdy_mask;
+ u8 status_register;
+ u8 trigger_register;
+ u32 mr_prescal_mask;
+ u32 mr_startup_mask;
+};
+
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);
+
+ u8 num_channels;
struct at91_adc_reg_desc registers;
};
@@ -67,6 +212,31 @@ 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;
+ u16 ts_pendbc;
+
+ bool ts_bufferedmeasure;
+ u32 ts_prev_absx;
+ u32 ts_prev_absy;
};
static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
@@ -83,13 +253,7 @@ static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
j++;
}
- if (idev->scan_timestamp) {
- s64 *timestamp = (s64 *)((u8 *)st->buffer +
- ALIGN(j, sizeof(s64)));
- *timestamp = pf->timestamp;
- }
-
- iio_push_to_buffers(idev, (u8 *)st->buffer);
+ iio_push_to_buffers_with_timestamp(idev, st->buffer, pf->timestamp);
iio_trigger_notify_done(idev->trig);
@@ -101,14 +265,10 @@ 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);
@@ -118,6 +278,180 @@ 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_rl_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);
+ unsigned int reg;
+
+ status &= at91_adc_readl(st, AT91_ADC_IMR);
+ if (status & st->registers->drdy_mask)
+ handle_adc_eoc_trigger(irq, idev);
+
+ if (status & AT91RL_ADC_IER_PEN) {
+ /* Disabling pen debounce is required to get a NOPEN irq */
+ reg = at91_adc_readl(st, AT91_ADC_MR);
+ reg &= ~AT91_ADC_PENDBC;
+ at91_adc_writel(st, AT91_ADC_MR, reg);
+
+ at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN);
+ at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_NOPEN
+ | AT91_ADC_EOC(3));
+ /* 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 & AT91RL_ADC_IER_NOPEN) {
+ reg = at91_adc_readl(st, AT91_ADC_MR);
+ reg |= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC;
+ at91_adc_writel(st, AT91_ADC_MR, reg);
+ at91_adc_writel(st, st->registers->trigger_register,
+ AT91_ADC_TRGR_NONE);
+
+ at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_NOPEN
+ | AT91_ADC_EOC(3));
+ at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN);
+ st->ts_bufferedmeasure = false;
+ input_report_key(st->ts_input, BTN_TOUCH, 0);
+ input_sync(st->ts_input);
+ } else if (status & AT91_ADC_EOC(3)) {
+ /* Conversion finished */
+ if (st->ts_bufferedmeasure) {
+ /*
+ * Last measurement is always discarded, since it can
+ * be erroneous.
+ * Always report previous measurement
+ */
+ input_report_abs(st->ts_input, ABS_X, st->ts_prev_absx);
+ input_report_abs(st->ts_input, ABS_Y, st->ts_prev_absy);
+ input_report_key(st->ts_input, BTN_TOUCH, 1);
+ input_sync(st->ts_input);
+ } else
+ st->ts_bufferedmeasure = true;
+
+ /* Now make new measurement */
+ st->ts_prev_absx = at91_adc_readl(st, AT91_ADC_CHAN(st, 3))
+ << MAX_RLPOS_BITS;
+ st->ts_prev_absx /= at91_adc_readl(st, AT91_ADC_CHAN(st, 2));
+
+ st->ts_prev_absy = at91_adc_readl(st, AT91_ADC_CHAN(st, 1))
+ << MAX_RLPOS_BITS;
+ st->ts_prev_absy /= at91_adc_readl(st, AT91_ADC_CHAN(st, 0));
+ }
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t at91_adc_9x5_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;
}
@@ -127,6 +461,16 @@ 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;
@@ -166,12 +510,11 @@ static int at91_adc_channel_init(struct iio_dev *idev)
return idev->num_channels;
}
-static u8 at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
+static int at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
struct at91_adc_trigger *triggers,
const char *trigger_name)
{
struct at91_adc_state *st = iio_priv(idev);
- u8 value = 0;
int i;
for (i = 0; i < st->trigger_number; i++) {
@@ -184,15 +527,16 @@ static u8 at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
return -ENOMEM;
if (strcmp(trigger_name, name) == 0) {
- value = triggers[i].value;
kfree(name);
- break;
+ if (triggers[i].value == 0)
+ return -EINVAL;
+ return triggers[i].value;
}
kfree(name);
}
- return value;
+ return -EINVAL;
}
static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
@@ -202,14 +546,14 @@ static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
struct iio_buffer *buffer = idev->buffer;
struct at91_adc_reg_desc *reg = st->registers;
u32 status = at91_adc_readl(st, reg->trigger_register);
- u8 value;
+ int value;
u8 bit;
value = at91_adc_get_trigger_value_by_name(idev,
st->trigger_list,
idev->trig->name);
- if (value == 0)
- return -EINVAL;
+ if (value < 0)
+ return value;
if (state) {
st->buffer = kmalloc(idev->scan_bytes, GFP_KERNEL);
@@ -279,7 +623,7 @@ static int at91_adc_trigger_init(struct iio_dev *idev)
int i, ret;
st->trig = devm_kzalloc(&idev->dev,
- st->trigger_number * sizeof(st->trig),
+ st->trigger_number * sizeof(*st->trig),
GFP_KERNEL);
if (st->trig == NULL) {
@@ -372,9 +716,9 @@ static int at91_adc_read_raw(struct iio_dev *idev,
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
- *val = (st->vref_mv * 1000) >> chan->scan_type.realbits;
- *val2 = 0;
- return IIO_VAL_INT_PLUS_MICRO;
+ *val = st->vref_mv;
+ *val2 = chan->scan_type.realbits;
+ return IIO_VAL_FRACTIONAL_LOG2;
default:
break;
}
@@ -434,8 +778,82 @@ ret:
return ret;
}
+static u32 calc_startup_ticks_9260(u8 startup_time, u32 adc_clk_khz)
+{
+ /*
+ * Number of ticks needed to cover the startup time of the ADC
+ * as defined in the electrical characteristics of the board,
+ * divided by 8. The formula thus is :
+ * Startup Time = (ticks + 1) * 8 / ADC Clock
+ */
+ return round_up((startup_time * adc_clk_khz / 1000) - 1, 8) / 8;
+}
+
+static u32 calc_startup_ticks_9x5(u8 startup_time, u32 adc_clk_khz)
+{
+ /*
+ * For sama5d3x and at91sam9x5, the formula changes to:
+ * Startup Time = <lookup_table_value> / ADC Clock
+ */
+ const int startup_lookup[] = {
+ 0 , 8 , 16 , 24 ,
+ 64 , 80 , 96 , 112,
+ 512, 576, 640, 704,
+ 768, 832, 896, 960
+ };
+ int i, size = ARRAY_SIZE(startup_lookup);
+ unsigned int ticks;
+
+ ticks = startup_time * adc_clk_khz / 1000;
+ for (i = 0; i < size; i++)
+ if (ticks < startup_lookup[i])
+ break;
+
+ ticks = i;
+ if (ticks == size)
+ /* Reach the end of lookup table */
+ ticks = size - 1;
+
+ return ticks;
+}
+
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;
+ }
+
+ if (!st->caps->has_tsmr)
+ return 0;
+ 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)
{
@@ -460,13 +878,6 @@ static int at91_adc_probe_dt(struct at91_adc_state *st,
}
st->channels_mask = prop;
- if (of_property_read_u32(node, "atmel,adc-num-channels", &prop)) {
- dev_err(&idev->dev, "Missing adc-num-channels property in the DT.\n");
- ret = -EINVAL;
- goto error_ret;
- }
- st->num_channels = prop;
-
st->sleep_mode = of_property_read_bool(node, "atmel,adc-sleep-mode");
if (of_property_read_u32(node, "atmel,adc-startup-time", &prop)) {
@@ -492,6 +903,7 @@ static int at91_adc_probe_dt(struct at91_adc_state *st,
goto error_ret;
st->registers = &st->caps->registers;
+ st->num_channels = st->caps->num_channels;
st->trigger_number = of_get_child_count(node);
st->trigger_list = devm_kzalloc(&idev->dev, st->trigger_number *
sizeof(struct at91_adc_trigger),
@@ -523,6 +935,12 @@ 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:
@@ -537,14 +955,18 @@ static int at91_adc_probe_pdata(struct at91_adc_state *st,
if (!pdata)
return -EINVAL;
+ st->caps = (struct at91_adc_caps *)
+ platform_get_device_id(pdev)->driver_data;
+
st->use_external = pdata->use_external_triggers;
st->vref_mv = pdata->vref;
st->channels_mask = pdata->channels_used;
- st->num_channels = pdata->num_channels;
+ st->num_channels = st->caps->num_channels;
st->startup_time = pdata->startup_time;
st->trigger_number = pdata->trigger_number;
st->trigger_list = pdata->trigger_list;
- st->registers = pdata->registers;
+ st->registers = &st->caps->registers;
+ st->touchscreen_type = pdata->touchscreen_type;
return 0;
}
@@ -554,6 +976,153 @@ 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);
+
+ if (st->caps->has_tsmr)
+ at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);
+ else
+ at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN);
+ return 0;
+}
+
+static void atmel_ts_close(struct input_dev *dev)
+{
+ struct at91_adc_state *st = input_get_drvdata(dev);
+
+ if (st->caps->has_tsmr)
+ at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);
+ else
+ at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN);
+}
+
+static int at91_ts_hw_init(struct at91_adc_state *st, u32 adc_clk_khz)
+{
+ u32 reg = 0;
+ int i = 0;
+
+ /* 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
+ */
+ st->ts_pendbc = round_up(TOUCH_PEN_DETECT_DEBOUNCE_US * adc_clk_khz /
+ 1000, 1);
+
+ while (st->ts_pendbc >> ++i)
+ ; /* Empty! Find the shift offset */
+ if (abs(st->ts_pendbc - (1 << i)) < abs(st->ts_pendbc - (1 << (i - 1))))
+ st->ts_pendbc = i;
+ else
+ st->ts_pendbc = i - 1;
+
+ if (!st->caps->has_tsmr) {
+ reg = at91_adc_readl(st, AT91_ADC_MR);
+ reg |= AT91_ADC_TSAMOD_TS_ONLY_MODE | AT91_ADC_PENDET;
+
+ reg |= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC;
+ at91_adc_writel(st, AT91_ADC_MR, reg);
+
+ reg = AT91_ADC_TSR_SHTIM_(TOUCH_SHTIM) & AT91_ADC_TSR_SHTIM;
+ at91_adc_writel(st, AT91_ADC_TSR, reg);
+
+ st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US_RL *
+ adc_clk_khz / 1000) - 1, 1);
+
+ return 0;
+ }
+
+ if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE)
+ reg = AT91_ADC_TSMR_TSMODE_4WIRE_PRESS;
+ else
+ reg = AT91_ADC_TSMR_TSMODE_5WIRE;
+
+ reg |= AT91_ADC_TSMR_TSAV_(st->caps->ts_filter_average)
+ & AT91_ADC_TSMR_TSAV;
+ reg |= AT91_ADC_TSMR_PENDBC_(st->ts_pendbc) & AT91_ADC_TSMR_PENDBC;
+ reg |= AT91_ADC_TSMR_NOTSDMA;
+ reg |= AT91_ADC_TSMR_PENDET_ENA;
+ reg |= 0x03 << 8; /* TSFREQ, needs to be bigger than TSAV */
+
+ at91_adc_writel(st, AT91_ADC_TSMR, reg);
+
+ /* 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 Period 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);
+ if (st->caps->has_tsmr) {
+ 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);
+ } else {
+ if (st->touchscreen_type != ATMEL_ADC_TOUCHSCREEN_4WIRE) {
+ dev_err(&pdev->dev,
+ "This touchscreen controller only support 4 wires\n");
+ ret = -EINVAL;
+ goto err;
+ }
+
+ input_set_abs_params(input, ABS_X, 0, (1 << MAX_RLPOS_BITS) - 1,
+ 0, 0);
+ input_set_abs_params(input, ABS_Y, 0, (1 << MAX_RLPOS_BITS) - 1,
+ 0, 0);
+ }
+
+ st->ts_input = input;
+ input_set_drvdata(input, st);
+
+ ret = input_register_device(input);
+ if (ret)
+ goto err;
+
+ return ret;
+
+err:
+ 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;
@@ -604,11 +1173,13 @@ 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,
- 0,
- pdev->dev.driver->name,
- idev);
+
+ if (st->caps->has_tsmr)
+ ret = request_irq(st->irq, at91_adc_9x5_interrupt, 0,
+ pdev->dev.driver->name, idev);
+ else
+ ret = request_irq(st->irq, at91_adc_rl_interrupt, 0,
+ pdev->dev.driver->name, idev);
if (ret) {
dev_err(&pdev->dev, "Failed to allocate IRQ.\n");
return ret;
@@ -650,6 +1221,10 @@ 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) {
@@ -657,21 +1232,18 @@ static int at91_adc_probe(struct platform_device *pdev)
ret = -EINVAL;
goto error_disable_adc_clk;
}
+ ticks = (*st->caps->calc_startup_ticks)(st->startup_time, adc_clk_khz);
/*
- * Number of ticks needed to cover the startup time of the ADC as
- * defined in the electrical characteristics of the board, divided by 8.
- * The formula thus is : Startup Time = (ticks + 1) * 8 / ADC Clock
- */
- ticks = round_up((st->startup_time * adc_clk_khz /
- 1000) - 1, 8) / 8;
- /*
* a minimal Sample and Hold Time is necessary for the ADC to guarantee
* the best converted final value between two channels selection
* The formula thus is : Sample and Hold Time = (shtim + 1) / ADCClock
*/
- shtim = round_up((st->sample_hold_time * adc_clk_khz /
- 1000) - 1, 1);
+ if (st->sample_hold_time > 0)
+ shtim = round_up((st->sample_hold_time * adc_clk_khz / 1000)
+ - 1, 1);
+ else
+ shtim = 0;
reg = AT91_ADC_PRESCAL_(prsc) & st->registers->mr_prescal_mask;
reg |= AT91_ADC_STARTUP_(ticks) & st->registers->mr_startup_mask;
@@ -692,30 +1264,47 @@ 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 {
+ 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:
@@ -731,8 +1320,12 @@ 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);
@@ -740,8 +1333,9 @@ static int at91_adc_remove(struct platform_device *pdev)
return 0;
}
-#ifdef CONFIG_OF
static struct at91_adc_caps at91sam9260_caps = {
+ .calc_startup_ticks = calc_startup_ticks_9260,
+ .num_channels = 4,
.registers = {
.channel_base = AT91_ADC_CHR(0),
.drdy_mask = AT91_ADC_DRDY,
@@ -752,7 +1346,24 @@ static struct at91_adc_caps at91sam9260_caps = {
},
};
+static struct at91_adc_caps at91sam9rl_caps = {
+ .has_ts = true,
+ .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */
+ .num_channels = 6,
+ .registers = {
+ .channel_base = AT91_ADC_CHR(0),
+ .drdy_mask = AT91_ADC_DRDY,
+ .status_register = AT91_ADC_SR,
+ .trigger_register = AT91_ADC_TRGR_9G45,
+ .mr_prescal_mask = AT91_ADC_PRESCAL_9260,
+ .mr_startup_mask = AT91_ADC_STARTUP_9G45,
+ },
+};
+
static struct at91_adc_caps at91sam9g45_caps = {
+ .has_ts = true,
+ .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */
+ .num_channels = 8,
.registers = {
.channel_base = AT91_ADC_CHR(0),
.drdy_mask = AT91_ADC_DRDY,
@@ -764,6 +1375,12 @@ 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 = {
.channel_base = AT91_ADC_CDR0_9X5,
.drdy_mask = AT91_ADC_SR_DRDY_9X5,
@@ -777,18 +1394,38 @@ static struct at91_adc_caps at91sam9x5_caps = {
static const struct of_device_id at91_adc_dt_ids[] = {
{ .compatible = "atmel,at91sam9260-adc", .data = &at91sam9260_caps },
+ { .compatible = "atmel,at91sam9rl-adc", .data = &at91sam9rl_caps },
{ .compatible = "atmel,at91sam9g45-adc", .data = &at91sam9g45_caps },
{ .compatible = "atmel,at91sam9x5-adc", .data = &at91sam9x5_caps },
{},
};
MODULE_DEVICE_TABLE(of, at91_adc_dt_ids);
-#endif
+
+static const struct platform_device_id at91_adc_ids[] = {
+ {
+ .name = "at91sam9260-adc",
+ .driver_data = (unsigned long)&at91sam9260_caps,
+ }, {
+ .name = "at91sam9rl-adc",
+ .driver_data = (unsigned long)&at91sam9rl_caps,
+ }, {
+ .name = "at91sam9g45-adc",
+ .driver_data = (unsigned long)&at91sam9g45_caps,
+ }, {
+ .name = "at91sam9x5-adc",
+ .driver_data = (unsigned long)&at91sam9x5_caps,
+ }, {
+ /* terminator */
+ }
+};
+MODULE_DEVICE_TABLE(platform, at91_adc_ids);
static struct platform_driver at91_adc_driver = {
.probe = at91_adc_probe,
.remove = at91_adc_remove,
+ .id_table = at91_adc_ids,
.driver = {
- .name = "at91_adc",
+ .name = DRIVER_NAME,
.of_match_table = of_match_ptr(at91_adc_dt_ids),
},
};