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authorLinus Torvalds <torvalds@linux-foundation.org>2013-11-07 15:07:58 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2013-11-07 15:07:58 +0900
commit0b1e73ed225d8f7aeef96b74147215ca8b990dce (patch)
treec362e187e34b8c1302fc1e6e6767b8790d44ed03 /drivers/iio/adc/ti_am335x_adc.c
parent56edff7529d0baa6d7b38b58f46631c7b9f4136e (diff)
parented5d6ca0038f274aada1244358ad89b7941bdcbf (diff)
Merge tag 'staging-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver update from Greg KH: "Here's the big drivers/staging/ update for 3.13-rc1. Nothing major here, just a _ton_ of fixes and cleanups, mostly driven by the new round of OPW applicants, but also there are lots of other people doing staging tree cleanups these days in order to help get the drivers into mergable shape. We also merge, and then revert, the ktap code, as Ingo and the other perf/ftrace developers feel it should go into the "real" part of the kernel with only a bit more work, so no need to put it in staging for now. All of this has been in linux-next for a while with no reported issues" * tag 'staging-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1045 commits) staging: drm/imx: fix return value check in ipu_add_subdevice_pdata() Staging: zram: Fix access of NULL pointer Staging: zram: Fix variable dereferenced before check Staging: rtl8187se: space prohibited before semicolon in r8185b_init.c Staging: rtl8187se: fix space prohibited after that open parenthesis '(' in r8185b_init.c Staging: rtl8187se: fix braces {} are not necessary for single statement blocks in r8185b_init.c Staging: rtl8187se: fix trailing whitespace in r8185b_init.c Staging: rtl8187se: fix please, no space before tabs in r8185b_init.c drivers/staging/nvec/Kconfig: remove trailing whitespace Staging: dwc2: Fix variable dereferenced before check Staging: xgifb: fix braces {} are not necessary for any arm of this statement staging: rtl8192e: remove unneeded semicolons staging: rtl8192e: use true and false for bool variables staging: ft1000: return values corrected in scram_start_dwnld staging: ft1000: change values of status return variable in write_dpram32_and_check staging: bcm: Remove unnecessary pointer casting imx-drm: ipuv3-crtc: Invert IPU DI0 clock polarity staging: r8188eu: Fix sparse warnings in rtl_p2p.c staging: r8188eu: Fix sparse warnings in rtw_mlme_ext.c staging: r8188eu: Fix sparse warnings in rtl8188e.cmd.c ...
Diffstat (limited to 'drivers/iio/adc/ti_am335x_adc.c')
-rw-r--r--drivers/iio/adc/ti_am335x_adc.c225
1 files changed, 207 insertions, 18 deletions
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index a952538a1a8b..728411ec7642 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -28,12 +28,16 @@
#include <linux/iio/driver.h>
#include <linux/mfd/ti_am335x_tscadc.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.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;
+ u16 data[8];
};
static unsigned int tiadc_readl(struct tiadc_device *adc, unsigned int reg)
@@ -56,8 +60,14 @@ 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 +82,11 @@ 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 +99,175 @@ 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 0;
+}
+
+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,
+};
+
+static 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",
@@ -120,9 +300,10 @@ 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 = 32;
+ chan->scan_type.storagebits = 16;
}
indio_dev->channels = chan_array;
@@ -142,11 +323,14 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
struct tiadc_device *adc_dev = iio_priv(indio_dev);
int i, map_val;
unsigned int fifo1count, read, stepid;
- u32 step = UINT_MAX;
bool found = false;
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);
@@ -168,15 +352,6 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
* Hence we need to flush out this data.
*/
- for (i = 0; i < ARRAY_SIZE(adc_dev->channel_step); i++) {
- if (chan->channel == adc_dev->channel_line[i]) {
- step = adc_dev->channel_step[i];
- break;
- }
- }
- if (WARN_ON_ONCE(step == UINT_MAX))
- return -EINVAL;
-
fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
for (i = 0; i < fifo1count; i++) {
read = tiadc_readl(adc_dev, REG_FIFO1);
@@ -186,7 +361,7 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
if (stepid == map_val) {
read = read & FIFOREAD_DATA_MASK;
found = true;
- *val = read;
+ *val = (u16) read;
}
}
@@ -237,20 +412,33 @@ 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 +451,7 @@ 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 +490,7 @@ 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;
}
@@ -326,7 +515,7 @@ static struct platform_driver tiadc_driver = {
.name = "TI-am335x-adc",
.owner = THIS_MODULE,
.pm = TIADC_PM_OPS,
- .of_match_table = of_match_ptr(ti_adc_dt_ids),
+ .of_match_table = ti_adc_dt_ids,
},
.probe = tiadc_probe,
.remove = tiadc_remove,