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path: root/drivers/input/touchscreen/ads7846.c
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Diffstat (limited to 'drivers/input/touchscreen/ads7846.c')
-rw-r--r--drivers/input/touchscreen/ads7846.c314
1 files changed, 196 insertions, 118 deletions
diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index 4bf2316e328..da201b8e37d 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -19,17 +19,21 @@
*/
#include <linux/types.h>
#include <linux/hwmon.h>
-#include <linux/init.h>
#include <linux/err.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
+#include <linux/pm.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/of_device.h>
#include <linux/gpio.h>
#include <linux/spi/spi.h>
#include <linux/spi/ads7846.h>
#include <linux/regulator/consumer.h>
+#include <linux/module.h>
#include <asm/irq.h>
/*
@@ -96,8 +100,7 @@ struct ads7846 {
struct spi_device *spi;
struct regulator *reg;
-#if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE)
- struct attribute_group *attr_group;
+#if IS_ENABLED(CONFIG_HWMON)
struct device *hwmon;
#endif
@@ -108,6 +111,7 @@ struct ads7846 {
u16 pressure_max;
bool swap_xy;
+ bool use_internal;
struct ads7846_packet *packet;
@@ -233,7 +237,12 @@ static void __ads7846_disable(struct ads7846 *ts)
/* Must be called with ts->lock held */
static void __ads7846_enable(struct ads7846 *ts)
{
- regulator_enable(ts->reg);
+ int error;
+
+ error = regulator_enable(ts->reg);
+ if (error != 0)
+ dev_err(&ts->spi->dev, "Failed to enable supply: %d\n", error);
+
ads7846_restart(ts);
}
@@ -280,17 +289,24 @@ struct ser_req {
u8 command;
u8 ref_off;
u16 scratch;
- __be16 sample;
struct spi_message msg;
struct spi_transfer xfer[6];
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ __be16 sample ____cacheline_aligned;
};
struct ads7845_ser_req {
u8 command[3];
- u8 pwrdown[3];
- u8 sample[3];
struct spi_message msg;
struct spi_transfer xfer[2];
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ u8 sample[3] ____cacheline_aligned;
};
static int ads7846_read12_ser(struct device *dev, unsigned command)
@@ -299,7 +315,6 @@ static int ads7846_read12_ser(struct device *dev, unsigned command)
struct ads7846 *ts = dev_get_drvdata(dev);
struct ser_req *req;
int status;
- int use_internal;
req = kzalloc(sizeof *req, GFP_KERNEL);
if (!req)
@@ -307,11 +322,8 @@ static int ads7846_read12_ser(struct device *dev, unsigned command)
spi_message_init(&req->msg);
- /* FIXME boards with ads7846 might use external vref instead ... */
- use_internal = (ts->model == 7846);
-
/* maybe turn on internal vREF, and let it settle */
- if (use_internal) {
+ if (ts->use_internal) {
req->ref_on = REF_ON;
req->xfer[0].tx_buf = &req->ref_on;
req->xfer[0].len = 1;
@@ -323,8 +335,14 @@ static int ads7846_read12_ser(struct device *dev, unsigned command)
/* for 1uF, settle for 800 usec; no cap, 100 usec. */
req->xfer[1].delay_usecs = ts->vref_delay_usecs;
spi_message_add_tail(&req->xfer[1], &req->msg);
+
+ /* Enable reference voltage */
+ command |= ADS_PD10_REF_ON;
}
+ /* Enable ADC in every case */
+ command |= ADS_PD10_ADC_ON;
+
/* take sample */
req->command = (u8) command;
req->xfer[2].tx_buf = &req->command;
@@ -401,14 +419,14 @@ static int ads7845_read12_ser(struct device *dev, unsigned command)
return status;
}
-#if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE)
+#if IS_ENABLED(CONFIG_HWMON)
#define SHOW(name, var, adjust) static ssize_t \
name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
struct ads7846 *ts = dev_get_drvdata(dev); \
- ssize_t v = ads7846_read12_ser(dev, \
- READ_12BIT_SER(var) | ADS_PD10_ALL_ON); \
+ ssize_t v = ads7846_read12_ser(&ts->spi->dev, \
+ READ_12BIT_SER(var)); \
if (v < 0) \
return v; \
return sprintf(buf, "%u\n", adjust(ts, v)); \
@@ -459,48 +477,43 @@ static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v)
SHOW(in0_input, vaux, vaux_adjust)
SHOW(in1_input, vbatt, vbatt_adjust)
-static struct attribute *ads7846_attributes[] = {
- &dev_attr_temp0.attr,
- &dev_attr_temp1.attr,
- &dev_attr_in0_input.attr,
- &dev_attr_in1_input.attr,
- NULL,
-};
-
-static struct attribute_group ads7846_attr_group = {
- .attrs = ads7846_attributes,
-};
+static umode_t ads7846_is_visible(struct kobject *kobj, struct attribute *attr,
+ int index)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct ads7846 *ts = dev_get_drvdata(dev);
-static struct attribute *ads7843_attributes[] = {
- &dev_attr_in0_input.attr,
- &dev_attr_in1_input.attr,
- NULL,
-};
+ if (ts->model == 7843 && index < 2) /* in0, in1 */
+ return 0;
+ if (ts->model == 7845 && index != 2) /* in0 */
+ return 0;
-static struct attribute_group ads7843_attr_group = {
- .attrs = ads7843_attributes,
-};
+ return attr->mode;
+}
-static struct attribute *ads7845_attributes[] = {
- &dev_attr_in0_input.attr,
+static struct attribute *ads7846_attributes[] = {
+ &dev_attr_temp0.attr, /* 0 */
+ &dev_attr_temp1.attr, /* 1 */
+ &dev_attr_in0_input.attr, /* 2 */
+ &dev_attr_in1_input.attr, /* 3 */
NULL,
};
-static struct attribute_group ads7845_attr_group = {
- .attrs = ads7845_attributes,
+static struct attribute_group ads7846_attr_group = {
+ .attrs = ads7846_attributes,
+ .is_visible = ads7846_is_visible,
};
+__ATTRIBUTE_GROUPS(ads7846_attr);
static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts)
{
- struct device *hwmon;
- int err;
-
/* hwmon sensors need a reference voltage */
switch (ts->model) {
case 7846:
if (!ts->vref_mv) {
dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n");
ts->vref_mv = 2500;
+ ts->use_internal = true;
}
break;
case 7845:
@@ -514,43 +527,19 @@ static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts)
break;
}
- /* different chips have different sensor groups */
- switch (ts->model) {
- case 7846:
- ts->attr_group = &ads7846_attr_group;
- break;
- case 7845:
- ts->attr_group = &ads7845_attr_group;
- break;
- case 7843:
- ts->attr_group = &ads7843_attr_group;
- break;
- default:
- dev_dbg(&spi->dev, "ADS%d not recognized\n", ts->model);
- return 0;
- }
-
- err = sysfs_create_group(&spi->dev.kobj, ts->attr_group);
- if (err)
- return err;
-
- hwmon = hwmon_device_register(&spi->dev);
- if (IS_ERR(hwmon)) {
- sysfs_remove_group(&spi->dev.kobj, ts->attr_group);
- return PTR_ERR(hwmon);
- }
+ ts->hwmon = hwmon_device_register_with_groups(&spi->dev, spi->modalias,
+ ts, ads7846_attr_groups);
+ if (IS_ERR(ts->hwmon))
+ return PTR_ERR(ts->hwmon);
- ts->hwmon = hwmon;
return 0;
}
static void ads784x_hwmon_unregister(struct spi_device *spi,
struct ads7846 *ts)
{
- if (ts->hwmon) {
- sysfs_remove_group(&spi->dev.kobj, ts->attr_group);
+ if (ts->hwmon)
hwmon_device_unregister(ts->hwmon);
- }
}
#else
@@ -589,10 +578,12 @@ static ssize_t ads7846_disable_store(struct device *dev,
const char *buf, size_t count)
{
struct ads7846 *ts = dev_get_drvdata(dev);
- unsigned long i;
+ unsigned int i;
+ int err;
- if (strict_strtoul(buf, 10, &i))
- return -EINVAL;
+ err = kstrtouint(buf, 10, &i);
+ if (err)
+ return err;
if (i)
ads7846_disable(ts);
@@ -715,7 +706,7 @@ static void ads7846_read_state(struct ads7846 *ts)
m = &ts->msg[msg_idx];
error = spi_sync(ts->spi, m);
if (error) {
- dev_err(&ts->spi->dev, "spi_async --> %d\n", error);
+ dev_err(&ts->spi->dev, "spi_sync --> %d\n", error);
packet->tc.ignore = true;
return;
}
@@ -892,9 +883,10 @@ static irqreturn_t ads7846_irq(int irq, void *handle)
return IRQ_HANDLED;
}
-static int ads7846_suspend(struct spi_device *spi, pm_message_t message)
+#ifdef CONFIG_PM_SLEEP
+static int ads7846_suspend(struct device *dev)
{
- struct ads7846 *ts = dev_get_drvdata(&spi->dev);
+ struct ads7846 *ts = dev_get_drvdata(dev);
mutex_lock(&ts->lock);
@@ -914,9 +906,9 @@ static int ads7846_suspend(struct spi_device *spi, pm_message_t message)
return 0;
}
-static int ads7846_resume(struct spi_device *spi)
+static int ads7846_resume(struct device *dev)
{
- struct ads7846 *ts = dev_get_drvdata(&spi->dev);
+ struct ads7846 *ts = dev_get_drvdata(dev);
mutex_lock(&ts->lock);
@@ -935,10 +927,14 @@ static int ads7846_resume(struct spi_device *spi)
return 0;
}
+#endif
-static int __devinit ads7846_setup_pendown(struct spi_device *spi, struct ads7846 *ts)
+static SIMPLE_DEV_PM_OPS(ads7846_pm, ads7846_suspend, ads7846_resume);
+
+static int ads7846_setup_pendown(struct spi_device *spi,
+ struct ads7846 *ts,
+ const struct ads7846_platform_data *pdata)
{
- struct ads7846_platform_data *pdata = spi->dev.platform_data;
int err;
/*
@@ -951,15 +947,20 @@ static int __devinit ads7846_setup_pendown(struct spi_device *spi, struct ads784
ts->get_pendown_state = pdata->get_pendown_state;
} else if (gpio_is_valid(pdata->gpio_pendown)) {
- err = gpio_request(pdata->gpio_pendown, "ads7846_pendown");
+ err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN,
+ "ads7846_pendown");
if (err) {
- dev_err(&spi->dev, "failed to request pendown GPIO%d\n",
- pdata->gpio_pendown);
+ dev_err(&spi->dev,
+ "failed to request/setup pendown GPIO%d: %d\n",
+ pdata->gpio_pendown, err);
return err;
}
ts->gpio_pendown = pdata->gpio_pendown;
+ if (pdata->gpio_pendown_debounce)
+ gpio_set_debounce(pdata->gpio_pendown,
+ pdata->gpio_pendown_debounce);
} else {
dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
return -EINVAL;
@@ -972,8 +973,8 @@ static int __devinit ads7846_setup_pendown(struct spi_device *spi, struct ads784
* Set up the transfers to read touchscreen state; this assumes we
* use formula #2 for pressure, not #3.
*/
-static void __devinit ads7846_setup_spi_msg(struct ads7846 *ts,
- const struct ads7846_platform_data *pdata)
+static void ads7846_setup_spi_msg(struct ads7846 *ts,
+ const struct ads7846_platform_data *pdata)
{
struct spi_message *m = &ts->msg[0];
struct spi_transfer *x = ts->xfer;
@@ -1171,33 +1172,107 @@ static void __devinit ads7846_setup_spi_msg(struct ads7846 *ts,
spi_message_add_tail(x, m);
}
-static int __devinit ads7846_probe(struct spi_device *spi)
+#ifdef CONFIG_OF
+static const struct of_device_id ads7846_dt_ids[] = {
+ { .compatible = "ti,tsc2046", .data = (void *) 7846 },
+ { .compatible = "ti,ads7843", .data = (void *) 7843 },
+ { .compatible = "ti,ads7845", .data = (void *) 7845 },
+ { .compatible = "ti,ads7846", .data = (void *) 7846 },
+ { .compatible = "ti,ads7873", .data = (void *) 7873 },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ads7846_dt_ids);
+
+static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
+{
+ struct ads7846_platform_data *pdata;
+ struct device_node *node = dev->of_node;
+ const struct of_device_id *match;
+
+ if (!node) {
+ dev_err(dev, "Device does not have associated DT data\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ match = of_match_device(ads7846_dt_ids, dev);
+ if (!match) {
+ dev_err(dev, "Unknown device model\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return ERR_PTR(-ENOMEM);
+
+ pdata->model = (unsigned long)match->data;
+
+ of_property_read_u16(node, "ti,vref-delay-usecs",
+ &pdata->vref_delay_usecs);
+ of_property_read_u16(node, "ti,vref-mv", &pdata->vref_mv);
+ pdata->keep_vref_on = of_property_read_bool(node, "ti,keep-vref-on");
+
+ pdata->swap_xy = of_property_read_bool(node, "ti,swap-xy");
+
+ of_property_read_u16(node, "ti,settle-delay-usec",
+ &pdata->settle_delay_usecs);
+ of_property_read_u16(node, "ti,penirq-recheck-delay-usecs",
+ &pdata->penirq_recheck_delay_usecs);
+
+ of_property_read_u16(node, "ti,x-plate-ohms", &pdata->x_plate_ohms);
+ of_property_read_u16(node, "ti,y-plate-ohms", &pdata->y_plate_ohms);
+
+ of_property_read_u16(node, "ti,x-min", &pdata->x_min);
+ of_property_read_u16(node, "ti,y-min", &pdata->y_min);
+ of_property_read_u16(node, "ti,x-max", &pdata->x_max);
+ of_property_read_u16(node, "ti,y-max", &pdata->y_max);
+
+ of_property_read_u16(node, "ti,pressure-min", &pdata->pressure_min);
+ of_property_read_u16(node, "ti,pressure-max", &pdata->pressure_max);
+
+ of_property_read_u16(node, "ti,debounce-max", &pdata->debounce_max);
+ of_property_read_u16(node, "ti,debounce-tol", &pdata->debounce_tol);
+ of_property_read_u16(node, "ti,debounce-rep", &pdata->debounce_rep);
+
+ of_property_read_u32(node, "ti,pendown-gpio-debounce",
+ &pdata->gpio_pendown_debounce);
+
+ pdata->wakeup = of_property_read_bool(node, "linux,wakeup");
+
+ pdata->gpio_pendown = of_get_named_gpio(dev->of_node, "pendown-gpio", 0);
+
+ return pdata;
+}
+#else
+static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
+{
+ dev_err(dev, "no platform data defined\n");
+ return ERR_PTR(-EINVAL);
+}
+#endif
+
+static int ads7846_probe(struct spi_device *spi)
{
+ const struct ads7846_platform_data *pdata;
struct ads7846 *ts;
struct ads7846_packet *packet;
struct input_dev *input_dev;
- struct ads7846_platform_data *pdata = spi->dev.platform_data;
unsigned long irq_flags;
int err;
if (!spi->irq) {
dev_dbg(&spi->dev, "no IRQ?\n");
- return -ENODEV;
- }
-
- if (!pdata) {
- dev_dbg(&spi->dev, "no platform data?\n");
- return -ENODEV;
+ return -EINVAL;
}
/* don't exceed max specified sample rate */
if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) {
- dev_dbg(&spi->dev, "f(sample) %d KHz?\n",
+ dev_err(&spi->dev, "f(sample) %d KHz?\n",
(spi->max_speed_hz/SAMPLE_BITS)/1000);
return -EINVAL;
}
- /* We'd set TX word size 8 bits and RX word size to 13 bits ... except
+ /*
+ * We'd set TX word size 8 bits and RX word size to 13 bits ... except
* that even if the hardware can do that, the SPI controller driver
* may not. So we stick to very-portable 8 bit words, both RX and TX.
*/
@@ -1215,22 +1290,30 @@ static int __devinit ads7846_probe(struct spi_device *spi)
goto err_free_mem;
}
- dev_set_drvdata(&spi->dev, ts);
+ spi_set_drvdata(spi, ts);
ts->packet = packet;
ts->spi = spi;
ts->input = input_dev;
- ts->vref_mv = pdata->vref_mv;
- ts->swap_xy = pdata->swap_xy;
mutex_init(&ts->lock);
init_waitqueue_head(&ts->wait);
+ pdata = dev_get_platdata(&spi->dev);
+ if (!pdata) {
+ pdata = ads7846_probe_dt(&spi->dev);
+ if (IS_ERR(pdata))
+ return PTR_ERR(pdata);
+ }
+
ts->model = pdata->model ? : 7846;
ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100;
ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
ts->pressure_max = pdata->pressure_max ? : ~0;
+ ts->vref_mv = pdata->vref_mv;
+ ts->swap_xy = pdata->swap_xy;
+
if (pdata->filter != NULL) {
if (pdata->filter_init != NULL) {
err = pdata->filter_init(pdata, &ts->filter_data);
@@ -1251,7 +1334,7 @@ static int __devinit ads7846_probe(struct spi_device *spi)
ts->filter = ads7846_no_filter;
}
- err = ads7846_setup_pendown(spi, ts);
+ err = ads7846_setup_pendown(spi, ts, pdata);
if (err)
goto err_cleanup_filter;
@@ -1328,8 +1411,7 @@ static int __devinit ads7846_probe(struct spi_device *spi)
if (ts->model == 7845)
ads7845_read12_ser(&spi->dev, PWRDOWN);
else
- (void) ads7846_read12_ser(&spi->dev,
- READ_12BIT_SER(vaux) | ADS_PD10_ALL_ON);
+ (void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux));
err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group);
if (err)
@@ -1341,6 +1423,13 @@ static int __devinit ads7846_probe(struct spi_device *spi)
device_init_wakeup(&spi->dev, pdata->wakeup);
+ /*
+ * If device does not carry platform data we must have allocated it
+ * when parsing DT data.
+ */
+ if (!dev_get_platdata(&spi->dev))
+ devm_kfree(&spi->dev, (void *)pdata);
+
return 0;
err_remove_attr_group:
@@ -1366,9 +1455,9 @@ static int __devinit ads7846_probe(struct spi_device *spi)
return err;
}
-static int __devexit ads7846_remove(struct spi_device *spi)
+static int ads7846_remove(struct spi_device *spi)
{
- struct ads7846 *ts = dev_get_drvdata(&spi->dev);
+ struct ads7846 *ts = spi_get_drvdata(spi);
device_init_wakeup(&spi->dev, false);
@@ -1406,26 +1495,15 @@ static int __devexit ads7846_remove(struct spi_device *spi)
static struct spi_driver ads7846_driver = {
.driver = {
.name = "ads7846",
- .bus = &spi_bus_type,
.owner = THIS_MODULE,
+ .pm = &ads7846_pm,
+ .of_match_table = of_match_ptr(ads7846_dt_ids),
},
.probe = ads7846_probe,
- .remove = __devexit_p(ads7846_remove),
- .suspend = ads7846_suspend,
- .resume = ads7846_resume,
+ .remove = ads7846_remove,
};
-static int __init ads7846_init(void)
-{
- return spi_register_driver(&ads7846_driver);
-}
-module_init(ads7846_init);
-
-static void __exit ads7846_exit(void)
-{
- spi_unregister_driver(&ads7846_driver);
-}
-module_exit(ads7846_exit);
+module_spi_driver(ads7846_driver);
MODULE_DESCRIPTION("ADS7846 TouchScreen Driver");
MODULE_LICENSE("GPL");
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 17:24:47 +0000