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-rw-r--r--drivers/iio/adc/Kconfig1
-rw-r--r--drivers/iio/adc/ti_am335x_adc.c213
-rw-r--r--include/linux/mfd/ti_am335x_tscadc.h9
3 files changed, 218 insertions, 5 deletions
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 0cf5c611b4c6..8b885188b839 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -177,6 +177,7 @@ config TI_ADC081C
config TI_AM335X_ADC
tristate "TI's AM335X ADC driver"
depends on MFD_TI_AM335X_TSCADC
+ select IIO_KFIFO_BUF
help
Say yes here to build support for Texas Instruments ADC
driver which is also a MFD client.
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index ebe93eba3ec8..5287bffd8a75 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -28,12 +28,20 @@
#include <linux/iio/driver.h>
#include <linux/mfd/ti_am335x_tscadc.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
struct tiadc_device {
struct ti_tscadc_dev *mfd_tscadc;
int channels;
u8 channel_line[8];
u8 channel_step[8];
+ int buffer_en_ch_steps;
+ struct iio_trigger *trig;
+ u16 data[8];
};
static unsigned int tiadc_readl(struct tiadc_device *adc, unsigned int reg)
@@ -56,8 +64,14 @@ static u32 get_adc_step_mask(struct tiadc_device *adc_dev)
return step_en;
}
-static void tiadc_step_config(struct tiadc_device *adc_dev)
+static u32 get_adc_step_bit(struct tiadc_device *adc_dev, int chan)
{
+ return 1 << adc_dev->channel_step[chan];
+}
+
+static void tiadc_step_config(struct iio_dev *indio_dev)
+{
+ struct tiadc_device *adc_dev = iio_priv(indio_dev);
unsigned int stepconfig;
int i, steps;
@@ -72,7 +86,11 @@ static void tiadc_step_config(struct tiadc_device *adc_dev)
*/
steps = TOTAL_STEPS - adc_dev->channels;
- stepconfig = STEPCONFIG_AVG_16 | STEPCONFIG_FIFO1;
+ if (iio_buffer_enabled(indio_dev))
+ stepconfig = STEPCONFIG_AVG_16 | STEPCONFIG_FIFO1
+ | STEPCONFIG_MODE_SWCNT;
+ else
+ stepconfig = STEPCONFIG_AVG_16 | STEPCONFIG_FIFO1;
for (i = 0; i < adc_dev->channels; i++) {
int chan;
@@ -85,9 +103,175 @@ static void tiadc_step_config(struct tiadc_device *adc_dev)
adc_dev->channel_step[i] = steps;
steps++;
}
+}
+
+static irqreturn_t tiadc_irq_h(int irq, void *private)
+{
+ struct iio_dev *indio_dev = private;
+ struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ unsigned int status, config;
+ status = tiadc_readl(adc_dev, REG_IRQSTATUS);
+
+ /*
+ * ADC and touchscreen share the IRQ line.
+ * FIFO0 interrupts are used by TSC. Handle FIFO1 IRQs here only
+ */
+ if (status & IRQENB_FIFO1OVRRUN) {
+ /* FIFO Overrun. Clear flag. Disable/Enable ADC to recover */
+ config = tiadc_readl(adc_dev, REG_CTRL);
+ config &= ~(CNTRLREG_TSCSSENB);
+ tiadc_writel(adc_dev, REG_CTRL, config);
+ tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1OVRRUN
+ | IRQENB_FIFO1UNDRFLW | IRQENB_FIFO1THRES);
+ tiadc_writel(adc_dev, REG_CTRL, (config | CNTRLREG_TSCSSENB));
+ return IRQ_HANDLED;
+ } else if (status & IRQENB_FIFO1THRES) {
+ /* Disable irq and wake worker thread */
+ tiadc_writel(adc_dev, REG_IRQCLR, IRQENB_FIFO1THRES);
+ return IRQ_WAKE_THREAD;
+ }
+
+ return IRQ_NONE;
+}
+
+static irqreturn_t tiadc_worker_h(int irq, void *private)
+{
+ struct iio_dev *indio_dev = private;
+ struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ int i, k, fifo1count, read;
+ u16 *data = adc_dev->data;
+
+ fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
+ for (k = 0; k < fifo1count; k = k + i) {
+ for (i = 0; i < (indio_dev->scan_bytes)/2; i++) {
+ read = tiadc_readl(adc_dev, REG_FIFO1);
+ data[i] = read & FIFOREAD_DATA_MASK;
+ }
+ iio_push_to_buffers(indio_dev, (u8 *) data);
+ }
+
+ tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1THRES);
+ tiadc_writel(adc_dev, REG_IRQENABLE, IRQENB_FIFO1THRES);
+
+ return IRQ_HANDLED;
+}
+
+static int tiadc_buffer_preenable(struct iio_dev *indio_dev)
+{
+ struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ int i, fifo1count, read;
+
+ tiadc_writel(adc_dev, REG_IRQCLR, (IRQENB_FIFO1THRES |
+ IRQENB_FIFO1OVRRUN |
+ IRQENB_FIFO1UNDRFLW));
+
+ /* Flush FIFO. Needed in corner cases in simultaneous tsc/adc use */
+ fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
+ for (i = 0; i < fifo1count; i++)
+ read = tiadc_readl(adc_dev, REG_FIFO1);
+
+ return iio_sw_buffer_preenable(indio_dev);
+}
+
+static int tiadc_buffer_postenable(struct iio_dev *indio_dev)
+{
+ struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ struct iio_buffer *buffer = indio_dev->buffer;
+ unsigned int enb = 0;
+ u8 bit;
+
+ tiadc_step_config(indio_dev);
+ for_each_set_bit(bit, buffer->scan_mask, adc_dev->channels)
+ enb |= (get_adc_step_bit(adc_dev, bit) << 1);
+ adc_dev->buffer_en_ch_steps = enb;
+
+ am335x_tsc_se_set(adc_dev->mfd_tscadc, enb);
+
+ tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1THRES
+ | IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW);
+ tiadc_writel(adc_dev, REG_IRQENABLE, IRQENB_FIFO1THRES
+ | IRQENB_FIFO1OVRRUN);
+
+ return 0;
+}
+
+static int tiadc_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ int fifo1count, i, read;
+
+ tiadc_writel(adc_dev, REG_IRQCLR, (IRQENB_FIFO1THRES |
+ IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW));
+ am335x_tsc_se_clr(adc_dev->mfd_tscadc, adc_dev->buffer_en_ch_steps);
+ /* Flush FIFO of leftover data in the time it takes to disable adc */
+ fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
+ for (i = 0; i < fifo1count; i++)
+ read = tiadc_readl(adc_dev, REG_FIFO1);
+
+ return 0;
}
+static int tiadc_buffer_postdisable(struct iio_dev *indio_dev)
+{
+ tiadc_step_config(indio_dev);
+
+ return 0;
+}
+
+static const struct iio_buffer_setup_ops tiadc_buffer_setup_ops = {
+ .preenable = &tiadc_buffer_preenable,
+ .postenable = &tiadc_buffer_postenable,
+ .predisable = &tiadc_buffer_predisable,
+ .postdisable = &tiadc_buffer_postdisable,
+};
+
+int tiadc_iio_buffered_hardware_setup(struct iio_dev *indio_dev,
+ irqreturn_t (*pollfunc_bh)(int irq, void *p),
+ irqreturn_t (*pollfunc_th)(int irq, void *p),
+ int irq,
+ unsigned long flags,
+ const struct iio_buffer_setup_ops *setup_ops)
+{
+ int ret;
+
+ indio_dev->buffer = iio_kfifo_allocate(indio_dev);
+ if (!indio_dev->buffer)
+ return -ENOMEM;
+
+ ret = request_threaded_irq(irq, pollfunc_th, pollfunc_bh,
+ flags, indio_dev->name, indio_dev);
+ if (ret)
+ goto error_kfifo_free;
+
+ indio_dev->setup_ops = setup_ops;
+ indio_dev->modes |= INDIO_BUFFER_HARDWARE;
+
+ ret = iio_buffer_register(indio_dev,
+ indio_dev->channels,
+ indio_dev->num_channels);
+ if (ret)
+ goto error_free_irq;
+
+ return 0;
+
+error_free_irq:
+ free_irq(irq, indio_dev);
+error_kfifo_free:
+ iio_kfifo_free(indio_dev->buffer);
+ return ret;
+}
+
+static void tiadc_iio_buffered_hardware_remove(struct iio_dev *indio_dev)
+{
+ struct tiadc_device *adc_dev = iio_priv(indio_dev);
+
+ free_irq(adc_dev->mfd_tscadc->irq, indio_dev);
+ iio_kfifo_free(indio_dev->buffer);
+ iio_buffer_unregister(indio_dev);
+}
+
+
static const char * const chan_name_ain[] = {
"AIN0",
"AIN1",
@@ -120,6 +304,7 @@ static int tiadc_channel_init(struct iio_dev *indio_dev, int channels)
chan->channel = adc_dev->channel_line[i];
chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
chan->datasheet_name = chan_name_ain[chan->channel];
+ chan->scan_index = i;
chan->scan_type.sign = 'u';
chan->scan_type.realbits = 12;
chan->scan_type.storagebits = 16;
@@ -147,6 +332,10 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
u32 step_en;
unsigned long timeout = jiffies + usecs_to_jiffies
(IDLE_TIMEOUT * adc_dev->channels);
+
+ if (iio_buffer_enabled(indio_dev))
+ return -EBUSY;
+
step_en = get_adc_step_mask(adc_dev);
am335x_tsc_se_set(adc_dev->mfd_tscadc, step_en);
@@ -237,20 +426,33 @@ static int tiadc_probe(struct platform_device *pdev)
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &tiadc_info;
- tiadc_step_config(adc_dev);
+ tiadc_step_config(indio_dev);
+ tiadc_writel(adc_dev, REG_FIFO1THR, FIFO1_THRESHOLD);
err = tiadc_channel_init(indio_dev, adc_dev->channels);
if (err < 0)
return err;
- err = iio_device_register(indio_dev);
+ err = tiadc_iio_buffered_hardware_setup(indio_dev,
+ &tiadc_worker_h,
+ &tiadc_irq_h,
+ adc_dev->mfd_tscadc->irq,
+ IRQF_SHARED,
+ &tiadc_buffer_setup_ops);
+
if (err)
goto err_free_channels;
+ err = iio_device_register(indio_dev);
+ if (err)
+ goto err_buffer_unregister;
+
platform_set_drvdata(pdev, indio_dev);
return 0;
+err_buffer_unregister:
+ tiadc_iio_buffered_hardware_remove(indio_dev);
err_free_channels:
tiadc_channels_remove(indio_dev);
return err;
@@ -263,6 +465,7 @@ static int tiadc_remove(struct platform_device *pdev)
u32 step_en;
iio_device_unregister(indio_dev);
+ tiadc_iio_buffered_hardware_remove(indio_dev);
tiadc_channels_remove(indio_dev);
step_en = get_adc_step_mask(adc_dev);
@@ -301,7 +504,7 @@ static int tiadc_resume(struct device *dev)
restore &= ~(CNTRLREG_POWERDOWN);
tiadc_writel(adc_dev, REG_CTRL, restore);
- tiadc_step_config(adc_dev);
+ tiadc_step_config(indio_dev);
return 0;
}
diff --git a/include/linux/mfd/ti_am335x_tscadc.h b/include/linux/mfd/ti_am335x_tscadc.h
index db1791bb997a..7d98562b3b51 100644
--- a/include/linux/mfd/ti_am335x_tscadc.h
+++ b/include/linux/mfd/ti_am335x_tscadc.h
@@ -46,16 +46,24 @@
/* Step Enable */
#define STEPENB_MASK (0x1FFFF << 0)
#define STEPENB(val) ((val) << 0)
+#define ENB(val) (1 << (val))
+#define STPENB_STEPENB STEPENB(0x1FFFF)
+#define STPENB_STEPENB_TC STEPENB(0x1FFF)
/* IRQ enable */
#define IRQENB_HW_PEN BIT(0)
#define IRQENB_FIFO0THRES BIT(2)
+#define IRQENB_FIFO0OVRRUN BIT(3)
+#define IRQENB_FIFO0UNDRFLW BIT(4)
#define IRQENB_FIFO1THRES BIT(5)
+#define IRQENB_FIFO1OVRRUN BIT(6)
+#define IRQENB_FIFO1UNDRFLW BIT(7)
#define IRQENB_PENUP BIT(9)
/* Step Configuration */
#define STEPCONFIG_MODE_MASK (3 << 0)
#define STEPCONFIG_MODE(val) ((val) << 0)
+#define STEPCONFIG_MODE_SWCNT STEPCONFIG_MODE(1)
#define STEPCONFIG_MODE_HWSYNC STEPCONFIG_MODE(2)
#define STEPCONFIG_AVG_MASK (7 << 2)
#define STEPCONFIG_AVG(val) ((val) << 2)
@@ -124,6 +132,7 @@
#define MAX_CLK_DIV 7
#define TOTAL_STEPS 16
#define TOTAL_CHANNELS 8
+#define FIFO1_THRESHOLD 19
/*
* ADC runs at 3MHz, and it takes
generated by cgit (git 2.34.1) at 2024-06-22 00:02:49 +0000