* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
-#include <linux/device.h>
+#include <linux/hwmon.h>
#include <linux/init.h>
+#include <linux/err.h>
#include <linux/delay.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
+#include <linux/gpio.h>
#include <linux/spi/spi.h>
#include <linux/spi/ads7846.h>
+#include <linux/regulator/consumer.h>
#include <asm/irq.h>
-#ifdef CONFIG_ARM
-#include <asm/mach-types.h>
-#ifdef CONFIG_ARCH_OMAP
-#include <asm/arch/gpio.h>
-#endif
-#endif
-
-
/*
* This code has been heavily tested on a Nokia 770, and lightly
- * tested on other ads7846 devices (OSK/Mistral, Lubbock).
- * Support for ads7843 and ads7845 has only been stubbed in.
+ * tested on other ads7846 devices (OSK/Mistral, Lubbock, Spitz).
+ * TSC2046 is just newer ads7846 silicon.
+ * Support for ads7843 tested on Atmel at91sam926x-EK.
+ * Support for ads7845 has only been stubbed in.
+ * Support for Analog Devices AD7873 and AD7843 tested.
*
* IRQ handling needs a workaround because of a shortcoming in handling
* edge triggered IRQs on some platforms like the OMAP1/2. These
* have to maintain our own SW IRQ disabled status. This should be
* removed as soon as the affected platform's IRQ handling is fixed.
*
- * app note sbaa036 talks in more detail about accurate sampling...
+ * App note sbaa036 talks in more detail about accurate sampling...
* that ought to help in situations like LCDs inducing noise (which
* can also be helped by using synch signals) and more generally.
* This driver tries to utilize the measures described in the app
* files.
*/
-#define TS_POLL_PERIOD msecs_to_jiffies(10)
+#define TS_POLL_DELAY (1 * 1000000) /* ns delay before the first sample */
+#define TS_POLL_PERIOD (5 * 1000000) /* ns delay between samples */
/* this driver doesn't aim at the peak continuous sample rate */
#define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */)
/* For portability, we can't read 12 bit values using SPI (which
* would make the controller deliver them as native byteorder u16
* with msbs zeroed). Instead, we read them as two 8-bit values,
- * which need byteswapping then range adjustment.
+ * *** WHICH NEED BYTESWAPPING *** and range adjustment.
*/
- __be16 x;
- __be16 y;
- __be16 z1, z2;
- int ignore;
+ u16 x;
+ u16 y;
+ u16 z1, z2;
+ int ignore;
+};
+
+/*
+ * We allocate this separately to avoid cache line sharing issues when
+ * driver is used with DMA-based SPI controllers (like atmel_spi) on
+ * systems where main memory is not DMA-coherent (most non-x86 boards).
+ */
+struct ads7846_packet {
+ u8 read_x, read_y, read_z1, read_z2, pwrdown;
+ u16 dummy; /* for the pwrdown read */
+ struct ts_event tc;
};
struct ads7846 {
struct input_dev *input;
char phys[32];
+ char name[32];
struct spi_device *spi;
+ struct regulator *reg;
+
+#if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE)
+ struct attribute_group *attr_group;
+ struct device *hwmon;
+#endif
+
u16 model;
+ u16 vref_mv;
u16 vref_delay_usecs;
u16 x_plate_ohms;
u16 pressure_max;
- u8 read_x, read_y, read_z1, read_z2, pwrdown;
- u16 dummy; /* for the pwrdown read */
- struct ts_event tc;
+ bool swap_xy;
+
+ struct ads7846_packet *packet;
- struct spi_transfer xfer[10];
+ struct spi_transfer xfer[18];
struct spi_message msg[5];
struct spi_message *last_msg;
int msg_idx;
u16 debounce_tol;
u16 debounce_rep;
+ u16 penirq_recheck_delay_usecs;
+
spinlock_t lock;
- struct timer_list timer; /* P: lock */
+ struct hrtimer timer;
unsigned pendown:1; /* P: lock */
unsigned pending:1; /* P: lock */
// FIXME remove "irq_disabled"
unsigned irq_disabled:1; /* P: lock */
unsigned disabled:1;
+ unsigned is_suspended:1;
+ int (*filter)(void *data, int data_idx, int *val);
+ void *filter_data;
+ void (*filter_cleanup)(void *data);
int (*get_pendown_state)(void);
+ int gpio_pendown;
+
+ void (*wait_for_sync)(void);
};
/* leave chip selected when we're done, for quicker re-select? */
#define MAX_12BIT ((1<<12)-1)
/* leave ADC powered up (disables penirq) between differential samples */
-#define READ_12BIT_DFR(x) (ADS_START | ADS_A2A1A0_d_ ## x \
- | ADS_12_BIT | ADS_DFR)
+#define READ_12BIT_DFR(x, adc, vref) (ADS_START | ADS_A2A1A0_d_ ## x \
+ | ADS_12_BIT | ADS_DFR | \
+ (adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0))
-#define READ_Y (READ_12BIT_DFR(y) | ADS_PD10_ADC_ON)
-#define READ_Z1 (READ_12BIT_DFR(z1) | ADS_PD10_ADC_ON)
-#define READ_Z2 (READ_12BIT_DFR(z2) | ADS_PD10_ADC_ON)
+#define READ_Y(vref) (READ_12BIT_DFR(y, 1, vref))
+#define READ_Z1(vref) (READ_12BIT_DFR(z1, 1, vref))
+#define READ_Z2(vref) (READ_12BIT_DFR(z2, 1, vref))
-#define READ_X (READ_12BIT_DFR(x) | ADS_PD10_ADC_ON)
-#define PWRDOWN (READ_12BIT_DFR(y) | ADS_PD10_PDOWN) /* LAST */
+#define READ_X(vref) (READ_12BIT_DFR(x, 1, vref))
+#define PWRDOWN (READ_12BIT_DFR(y, 0, 0)) /* LAST */
/* single-ended samples need to first power up reference voltage;
* we leave both ADC and VREF powered
#define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \
| ADS_12_BIT | ADS_SER)
-#define REF_ON (READ_12BIT_DFR(x) | ADS_PD10_ALL_ON)
-#define REF_OFF (READ_12BIT_DFR(y) | ADS_PD10_PDOWN)
+#define REF_ON (READ_12BIT_DFR(x, 1, 1))
+#define REF_OFF (READ_12BIT_DFR(y, 0, 0))
/*--------------------------------------------------------------------------*/
/*
* Non-touchscreen sensors only use single-ended conversions.
+ * The range is GND..vREF. The ads7843 and ads7835 must use external vREF;
+ * ads7846 lets that pin be unconnected, to use internal vREF.
*/
struct ser_req {
static int device_suspended(struct device *dev)
{
struct ads7846 *ts = dev_get_drvdata(dev);
- return dev->power.power_state.event != PM_EVENT_ON || ts->disabled;
+ return ts->is_suspended || ts->disabled;
}
static int ads7846_read12_ser(struct device *dev, unsigned command)
{
struct spi_device *spi = to_spi_device(dev);
struct ads7846 *ts = dev_get_drvdata(dev);
- struct ser_req *req = kzalloc(sizeof *req, SLAB_KERNEL);
+ struct ser_req *req = kzalloc(sizeof *req, GFP_KERNEL);
int status;
- int sample;
- int i;
+ int use_internal;
if (!req)
return -ENOMEM;
spi_message_init(&req->msg);
- /* activate reference, so it has time to settle; */
- req->ref_on = REF_ON;
- req->xfer[0].tx_buf = &req->ref_on;
- req->xfer[0].len = 1;
- req->xfer[1].rx_buf = &req->scratch;
- req->xfer[1].len = 2;
-
- /*
- * for external VREF, 0 usec (and assume it's always on);
- * for 1uF, use 800 usec;
- * no cap, 100 usec.
- */
- req->xfer[1].delay_usecs = ts->vref_delay_usecs;
+ /* 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) {
+ req->ref_on = REF_ON;
+ req->xfer[0].tx_buf = &req->ref_on;
+ req->xfer[0].len = 1;
+ spi_message_add_tail(&req->xfer[0], &req->msg);
+
+ req->xfer[1].rx_buf = &req->scratch;
+ req->xfer[1].len = 2;
+
+ /* 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);
+ }
/* take sample */
req->command = (u8) command;
req->xfer[2].tx_buf = &req->command;
req->xfer[2].len = 1;
+ spi_message_add_tail(&req->xfer[2], &req->msg);
+
req->xfer[3].rx_buf = &req->sample;
req->xfer[3].len = 2;
+ spi_message_add_tail(&req->xfer[3], &req->msg);
/* REVISIT: take a few more samples, and compare ... */
- /* turn off reference */
- req->ref_off = REF_OFF;
+ /* converter in low power mode & enable PENIRQ */
+ req->ref_off = PWRDOWN;
req->xfer[4].tx_buf = &req->ref_off;
req->xfer[4].len = 1;
+ spi_message_add_tail(&req->xfer[4], &req->msg);
+
req->xfer[5].rx_buf = &req->scratch;
req->xfer[5].len = 2;
-
CS_CHANGE(req->xfer[5]);
-
- /* group all the transfers together, so we can't interfere with
- * reading touchscreen state; disable penirq while sampling
- */
- for (i = 0; i < 6; i++)
- spi_message_add_tail(&req->xfer[i], &req->msg);
+ spi_message_add_tail(&req->xfer[5], &req->msg);
ts->irq_disabled = 1;
disable_irq(spi->irq);
ts->irq_disabled = 0;
enable_irq(spi->irq);
- if (req->msg.status)
- status = req->msg.status;
-
- /* on-wire is a must-ignore bit, a BE12 value, then padding */
- sample = be16_to_cpu(req->sample);
- sample = sample >> 3;
- sample &= 0x0fff;
+ if (status == 0) {
+ /* on-wire is a must-ignore bit, a BE12 value, then padding */
+ status = be16_to_cpu(req->sample);
+ status = status >> 3;
+ status &= 0x0fff;
+ }
kfree(req);
- return status ? status : sample;
+ return status;
}
-#define SHOW(name) static ssize_t \
+#if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE)
+
+#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(name) | ADS_PD10_ALL_ON); \
+ READ_12BIT_SER(var) | ADS_PD10_ALL_ON); \
if (v < 0) \
return v; \
- return sprintf(buf, "%u\n", (unsigned) v); \
+ return sprintf(buf, "%u\n", adjust(ts, v)); \
} \
static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL);
-SHOW(temp0)
-SHOW(temp1)
-SHOW(vaux)
-SHOW(vbatt)
+
+/* Sysfs conventions report temperatures in millidegrees Celsius.
+ * ADS7846 could use the low-accuracy two-sample scheme, but can't do the high
+ * accuracy scheme without calibration data. For now we won't try either;
+ * userspace sees raw sensor values, and must scale/calibrate appropriately.
+ */
+static inline unsigned null_adjust(struct ads7846 *ts, ssize_t v)
+{
+ return v;
+}
+
+SHOW(temp0, temp0, null_adjust) /* temp1_input */
+SHOW(temp1, temp1, null_adjust) /* temp2_input */
+
+
+/* sysfs conventions report voltages in millivolts. We can convert voltages
+ * if we know vREF. userspace may need to scale vAUX to match the board's
+ * external resistors; we assume that vBATT only uses the internal ones.
+ */
+static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v)
+{
+ unsigned retval = v;
+
+ /* external resistors may scale vAUX into 0..vREF */
+ retval *= ts->vref_mv;
+ retval = retval >> 12;
+ return retval;
+}
+
+static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v)
+{
+ unsigned retval = vaux_adjust(ts, v);
+
+ /* ads7846 has a resistor ladder to scale this signal down */
+ if (ts->model == 7846)
+ retval *= 4;
+ return retval;
+}
+
+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 struct attribute *ads7843_attributes[] = {
+ &dev_attr_in0_input.attr,
+ &dev_attr_in1_input.attr,
+ NULL,
+};
+
+static struct attribute_group ads7843_attr_group = {
+ .attrs = ads7843_attributes,
+};
+
+static struct attribute *ads7845_attributes[] = {
+ &dev_attr_in0_input.attr,
+ NULL,
+};
+
+static struct attribute_group ads7845_attr_group = {
+ .attrs = ads7845_attributes,
+};
+
+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;
+ }
+ break;
+ case 7845:
+ case 7843:
+ if (!ts->vref_mv) {
+ dev_warn(&spi->dev,
+ "external vREF for ADS%d not specified\n",
+ ts->model);
+ return 0;
+ }
+ 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;
+ 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);
+ hwmon_device_unregister(ts->hwmon);
+ }
+}
+
+#else
+static inline int ads784x_hwmon_register(struct spi_device *spi,
+ struct ads7846 *ts)
+{
+ return 0;
+}
+
+static inline void ads784x_hwmon_unregister(struct spi_device *spi,
+ struct ads7846 *ts)
+{
+}
+#endif
static int is_pen_down(struct device *dev)
{
- struct ads7846 *ts = dev_get_drvdata(dev);
+ struct ads7846 *ts = dev_get_drvdata(dev);
return ts->pendown;
}
const char *buf, size_t count)
{
struct ads7846 *ts = dev_get_drvdata(dev);
- char *endp;
- int i;
+ unsigned long i;
+
+ if (strict_strtoul(buf, 10, &i))
+ return -EINVAL;
- i = simple_strtoul(buf, &endp, 10);
spin_lock_irq(&ts->lock);
if (i)
static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store);
+static struct attribute *ads784x_attributes[] = {
+ &dev_attr_pen_down.attr,
+ &dev_attr_disable.attr,
+ NULL,
+};
+
+static struct attribute_group ads784x_attr_group = {
+ .attrs = ads784x_attributes,
+};
+
/*--------------------------------------------------------------------------*/
+static int get_pendown_state(struct ads7846 *ts)
+{
+ if (ts->get_pendown_state)
+ return ts->get_pendown_state();
+
+ return !gpio_get_value(ts->gpio_pendown);
+}
+
+static void null_wait_for_sync(void)
+{
+}
+
/*
* PENIRQ only kicks the timer. The timer only reissues the SPI transfer,
* to retrieve touchscreen status.
static void ads7846_rx(void *ads)
{
struct ads7846 *ts = ads;
- struct input_dev *input_dev = ts->input;
+ struct ads7846_packet *packet = ts->packet;
unsigned Rt;
- unsigned sync = 0;
u16 x, y, z1, z2;
- unsigned long flags;
- /* adjust: on-wire is a must-ignore bit, a BE12 value, then padding;
- * built from two 8 bit values written msb-first.
+ /* ads7846_rx_val() did in-place conversion (including byteswap) from
+ * on-the-wire format as part of debouncing to get stable readings.
*/
- x = (be16_to_cpu(ts->tc.x) >> 3) & 0x0fff;
- y = (be16_to_cpu(ts->tc.y) >> 3) & 0x0fff;
- z1 = (be16_to_cpu(ts->tc.z1) >> 3) & 0x0fff;
- z2 = (be16_to_cpu(ts->tc.z2) >> 3) & 0x0fff;
+ x = packet->tc.x;
+ y = packet->tc.y;
+ z1 = packet->tc.z1;
+ z2 = packet->tc.z2;
/* range filtering */
if (x == MAX_12BIT)
x = 0;
- if (likely(x && z1 && !device_suspended(&ts->spi->dev))) {
+ if (ts->model == 7843) {
+ Rt = ts->pressure_max / 2;
+ } else if (likely(x && z1)) {
/* compute touch pressure resistance using equation #2 */
Rt = z2;
Rt -= z1;
Rt *= ts->x_plate_ohms;
Rt /= z1;
Rt = (Rt + 2047) >> 12;
- } else
+ } else {
Rt = 0;
+ }
/* Sample found inconsistent by debouncing or pressure is beyond
- * the maximum. Don't report it to user space, repeat at least
- * once more the measurement */
- if (ts->tc.ignore || Rt > ts->pressure_max) {
- mod_timer(&ts->timer, jiffies + TS_POLL_PERIOD);
+ * the maximum. Don't report it to user space, repeat at least
+ * once more the measurement
+ */
+ if (packet->tc.ignore || Rt > ts->pressure_max) {
+ dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n",
+ packet->tc.ignore, Rt);
+ hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
+ HRTIMER_MODE_REL);
return;
}
- /* NOTE: "pendown" is inferred from pressure; we don't rely on
- * being able to check nPENIRQ status, or "friendly" trigger modes
- * (both-edges is much better than just-falling or low-level).
- *
- * REVISIT: some boards may require reading nPENIRQ; it's
- * needed on 7843. and 7845 reads pressure differently...
- *
- * REVISIT: the touchscreen might not be connected; this code
- * won't notice that, even if nPENIRQ never fires ...
+ /* Maybe check the pendown state before reporting. This discards
+ * false readings when the pen is lifted.
*/
- if (!ts->pendown && Rt != 0) {
- input_report_key(input_dev, BTN_TOUCH, 1);
- sync = 1;
- } else if (ts->pendown && Rt == 0) {
- input_report_key(input_dev, BTN_TOUCH, 0);
- sync = 1;
+ if (ts->penirq_recheck_delay_usecs) {
+ udelay(ts->penirq_recheck_delay_usecs);
+ if (!get_pendown_state(ts))
+ Rt = 0;
}
+ /* NOTE: We can't rely on the pressure to determine the pen down
+ * state, even this controller has a pressure sensor. The pressure
+ * value can fluctuate for quite a while after lifting the pen and
+ * in some cases may not even settle at the expected value.
+ *
+ * The only safe way to check for the pen up condition is in the
+ * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
+ */
if (Rt) {
- input_report_abs(input_dev, ABS_X, x);
- input_report_abs(input_dev, ABS_Y, y);
- sync = 1;
- }
+ struct input_dev *input = ts->input;
- if (sync) {
- input_report_abs(input_dev, ABS_PRESSURE, Rt);
- input_sync(input_dev);
- }
+ if (!ts->pendown) {
+ input_report_key(input, BTN_TOUCH, 1);
+ ts->pendown = 1;
+ dev_vdbg(&ts->spi->dev, "DOWN\n");
+ }
-#ifdef VERBOSE
- if (Rt || ts->pendown)
- pr_debug("%s: %d/%d/%d%s\n", ts->spi->dev.bus_id,
- x, y, Rt, Rt ? "" : " UP");
-#endif
+ if (ts->swap_xy)
+ swap(x, y);
- spin_lock_irqsave(&ts->lock, flags);
+ input_report_abs(input, ABS_X, x);
+ input_report_abs(input, ABS_Y, y);
+ input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt);
- ts->pendown = (Rt != 0);
- mod_timer(&ts->timer, jiffies + TS_POLL_PERIOD);
+ input_sync(input);
+ dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt);
+ }
- spin_unlock_irqrestore(&ts->lock, flags);
+ hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
+ HRTIMER_MODE_REL);
}
-static void ads7846_debounce(void *ads)
+static int ads7846_debounce(void *ads, int data_idx, int *val)
{
struct ads7846 *ts = ads;
- struct spi_message *m;
- struct spi_transfer *t;
- int val;
- int status;
- m = &ts->msg[ts->msg_idx];
- t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list);
- val = (be16_to_cpu(*(__be16 *)t->rx_buf) >> 3) & 0x0fff;
- if (!ts->read_cnt || (abs(ts->last_read - val) > ts->debounce_tol)) {
+ if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) {
+ /* Start over collecting consistent readings. */
+ ts->read_rep = 0;
/* Repeat it, if this was the first read or the read
* wasn't consistent enough. */
if (ts->read_cnt < ts->debounce_max) {
- ts->last_read = val;
+ ts->last_read = *val;
ts->read_cnt++;
+ return ADS7846_FILTER_REPEAT;
} else {
/* Maximum number of debouncing reached and still
* not enough number of consistent readings. Abort
* the whole sample, repeat it in the next sampling
* period.
*/
- ts->tc.ignore = 1;
ts->read_cnt = 0;
- /* Last message will contain ads7846_rx() as the
- * completion function.
- */
- m = ts->last_msg;
+ return ADS7846_FILTER_IGNORE;
}
- /* Start over collecting consistent readings. */
- ts->read_rep = 0;
} else {
if (++ts->read_rep > ts->debounce_rep) {
/* Got a good reading for this coordinate,
* go for the next one. */
- ts->tc.ignore = 0;
- ts->msg_idx++;
ts->read_cnt = 0;
ts->read_rep = 0;
- m++;
- } else
+ return ADS7846_FILTER_OK;
+ } else {
/* Read more values that are consistent. */
ts->read_cnt++;
+ return ADS7846_FILTER_REPEAT;
+ }
+ }
+}
+
+static int ads7846_no_filter(void *ads, int data_idx, int *val)
+{
+ return ADS7846_FILTER_OK;
+}
+
+static void ads7846_rx_val(void *ads)
+{
+ struct ads7846 *ts = ads;
+ struct ads7846_packet *packet = ts->packet;
+ struct spi_message *m;
+ struct spi_transfer *t;
+ int val;
+ int action;
+ int status;
+
+ m = &ts->msg[ts->msg_idx];
+ t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list);
+
+ /* adjust: on-wire is a must-ignore bit, a BE12 value, then padding;
+ * built from two 8 bit values written msb-first.
+ */
+ val = be16_to_cpup((__be16 *)t->rx_buf) >> 3;
+
+ action = ts->filter(ts->filter_data, ts->msg_idx, &val);
+ switch (action) {
+ case ADS7846_FILTER_REPEAT:
+ break;
+ case ADS7846_FILTER_IGNORE:
+ packet->tc.ignore = 1;
+ /* Last message will contain ads7846_rx() as the
+ * completion function.
+ */
+ m = ts->last_msg;
+ break;
+ case ADS7846_FILTER_OK:
+ *(u16 *)t->rx_buf = val;
+ packet->tc.ignore = 0;
+ m = &ts->msg[++ts->msg_idx];
+ break;
+ default:
+ BUG();
}
+ ts->wait_for_sync();
status = spi_async(ts->spi, m);
if (status)
dev_err(&ts->spi->dev, "spi_async --> %d\n",
status);
}
-static void ads7846_timer(unsigned long handle)
+static enum hrtimer_restart ads7846_timer(struct hrtimer *handle)
{
- struct ads7846 *ts = (void *)handle;
+ struct ads7846 *ts = container_of(handle, struct ads7846, timer);
int status = 0;
- spin_lock_irq(&ts->lock);
+ spin_lock(&ts->lock);
+
+ if (unlikely(!get_pendown_state(ts) ||
+ device_suspended(&ts->spi->dev))) {
+ if (ts->pendown) {
+ struct input_dev *input = ts->input;
+
+ input_report_key(input, BTN_TOUCH, 0);
+ input_report_abs(input, ABS_PRESSURE, 0);
+ input_sync(input);
+
+ ts->pendown = 0;
+ dev_vdbg(&ts->spi->dev, "UP\n");
+ }
- if (unlikely(ts->msg_idx && !ts->pendown)) {
/* measurement cycle ended */
if (!device_suspended(&ts->spi->dev)) {
ts->irq_disabled = 0;
enable_irq(ts->spi->irq);
}
ts->pending = 0;
- ts->msg_idx = 0;
} else {
/* pen is still down, continue with the measurement */
ts->msg_idx = 0;
+ ts->wait_for_sync();
status = spi_async(ts->spi, &ts->msg[0]);
if (status)
dev_err(&ts->spi->dev, "spi_async --> %d\n", status);
}
- spin_unlock_irq(&ts->lock);
+ spin_unlock(&ts->lock);
+ return HRTIMER_NORESTART;
}
static irqreturn_t ads7846_irq(int irq, void *handle)
unsigned long flags;
spin_lock_irqsave(&ts->lock, flags);
- if (likely(ts->get_pendown_state())) {
+ if (likely(get_pendown_state(ts))) {
if (!ts->irq_disabled) {
/* The ARM do_simple_IRQ() dispatcher doesn't act
* like the other dispatchers: it will report IRQs
* that here. (The "generic irq" framework may help...)
*/
ts->irq_disabled = 1;
- disable_irq(ts->spi->irq);
+ disable_irq_nosync(ts->spi->irq);
ts->pending = 1;
- mod_timer(&ts->timer, jiffies);
+ hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY),
+ HRTIMER_MODE_REL);
}
}
spin_unlock_irqrestore(&ts->lock, flags);
}
}
+ regulator_disable(ts->reg);
+
/* we know the chip's in lowpower mode since we always
* leave it that way after every request
*/
-
}
/* Must be called with ts->lock held */
if (!ts->disabled)
return;
+ regulator_enable(ts->reg);
+
ts->disabled = 0;
ts->irq_disabled = 0;
enable_irq(ts->spi->irq);
spin_lock_irq(&ts->lock);
- spi->dev.power.power_state = message;
+ ts->is_suspended = 1;
ads7846_disable(ts);
spin_unlock_irq(&ts->lock);
+ if (device_may_wakeup(&ts->spi->dev))
+ enable_irq_wake(ts->spi->irq);
+
return 0;
}
{
struct ads7846 *ts = dev_get_drvdata(&spi->dev);
+ if (device_may_wakeup(&ts->spi->dev))
+ disable_irq_wake(ts->spi->irq);
+
spin_lock_irq(&ts->lock);
- spi->dev.power.power_state = PMSG_ON;
+ ts->is_suspended = 0;
ads7846_enable(ts);
spin_unlock_irq(&ts->lock);
return 0;
}
+static int __devinit setup_pendown(struct spi_device *spi, struct ads7846 *ts)
+{
+ struct ads7846_platform_data *pdata = spi->dev.platform_data;
+ int err;
+
+ /* REVISIT when the irq can be triggered active-low, or if for some
+ * reason the touchscreen isn't hooked up, we don't need to access
+ * the pendown state.
+ */
+ if (!pdata->get_pendown_state && !gpio_is_valid(pdata->gpio_pendown)) {
+ dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
+ return -EINVAL;
+ }
+
+ if (pdata->get_pendown_state) {
+ ts->get_pendown_state = pdata->get_pendown_state;
+ return 0;
+ }
+
+ err = gpio_request(pdata->gpio_pendown, "ads7846_pendown");
+ if (err) {
+ dev_err(&spi->dev, "failed to request pendown GPIO%d\n",
+ pdata->gpio_pendown);
+ return err;
+ }
+
+ ts->gpio_pendown = pdata->gpio_pendown;
+ return 0;
+}
+
static int __devinit ads7846_probe(struct spi_device *spi)
{
struct ads7846 *ts;
+ struct ads7846_packet *packet;
struct input_dev *input_dev;
struct ads7846_platform_data *pdata = spi->dev.platform_data;
struct spi_message *m;
struct spi_transfer *x;
+ int vref;
int err;
if (!spi->irq) {
return -EINVAL;
}
- /* REVISIT when the irq can be triggered active-low, or if for some
- * reason the touchscreen isn't hooked up, we don't need to access
- * the pendown state.
- */
- if (pdata->get_pendown_state == NULL) {
- dev_dbg(&spi->dev, "no get_pendown_state function?\n");
- return -EINVAL;
- }
-
/* We'd set TX wordsize 8 bits and RX wordsize 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.
*/
spi->bits_per_word = 8;
+ spi->mode = SPI_MODE_0;
+ err = spi_setup(spi);
+ if (err < 0)
+ return err;
ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL);
+ packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL);
input_dev = input_allocate_device();
- if (!ts || !input_dev) {
+ if (!ts || !packet || !input_dev) {
err = -ENOMEM;
goto err_free_mem;
}
dev_set_drvdata(&spi->dev, ts);
- spi->dev.power.power_state = PMSG_ON;
+ ts->packet = packet;
ts->spi = spi;
ts->input = input_dev;
+ ts->vref_mv = pdata->vref_mv;
+ ts->swap_xy = pdata->swap_xy;
- init_timer(&ts->timer);
- ts->timer.data = (unsigned long) ts;
+ hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
ts->timer.function = ads7846_timer;
spin_lock_init(&ts->lock);
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;
- if (pdata->debounce_max) {
+
+ if (pdata->filter != NULL) {
+ if (pdata->filter_init != NULL) {
+ err = pdata->filter_init(pdata, &ts->filter_data);
+ if (err < 0)
+ goto err_free_mem;
+ }
+ ts->filter = pdata->filter;
+ ts->filter_cleanup = pdata->filter_cleanup;
+ } else if (pdata->debounce_max) {
ts->debounce_max = pdata->debounce_max;
+ if (ts->debounce_max < 2)
+ ts->debounce_max = 2;
ts->debounce_tol = pdata->debounce_tol;
ts->debounce_rep = pdata->debounce_rep;
- if (ts->debounce_rep > ts->debounce_max + 1)
- ts->debounce_rep = ts->debounce_max - 1;
+ ts->filter = ads7846_debounce;
+ ts->filter_data = ts;
} else
- ts->debounce_tol = ~0;
- ts->get_pendown_state = pdata->get_pendown_state;
+ ts->filter = ads7846_no_filter;
- snprintf(ts->phys, sizeof(ts->phys), "%s/input0", spi->dev.bus_id);
+ err = setup_pendown(spi, ts);
+ if (err)
+ goto err_cleanup_filter;
+
+ if (pdata->penirq_recheck_delay_usecs)
+ ts->penirq_recheck_delay_usecs =
+ pdata->penirq_recheck_delay_usecs;
+
+ ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync;
+
+ snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev));
+ snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model);
- input_dev->name = "ADS784x Touchscreen";
+ input_dev->name = ts->name;
input_dev->phys = ts->phys;
- input_dev->cdev.dev = &spi->dev;
+ input_dev->dev.parent = &spi->dev;
- input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
- input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
+ input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+ input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
input_set_abs_params(input_dev, ABS_X,
pdata->x_min ? : 0,
pdata->x_max ? : MAX_12BIT,
input_set_abs_params(input_dev, ABS_PRESSURE,
pdata->pressure_min, pdata->pressure_max, 0, 0);
+ vref = pdata->keep_vref_on;
+
+ if (ts->model == 7873) {
+ /* The AD7873 is almost identical to the ADS7846
+ * keep VREF off during differential/ratiometric
+ * conversion modes
+ */
+ ts->model = 7846;
+ vref = 0;
+ }
+
/* set up the transfers to read touchscreen state; this assumes we
* use formula #2 for pressure, not #3.
*/
spi_message_init(m);
/* y- still on; turn on only y+ (and ADC) */
- ts->read_y = READ_Y;
- x->tx_buf = &ts->read_y;
+ packet->read_y = READ_Y(vref);
+ x->tx_buf = &packet->read_y;
x->len = 1;
spi_message_add_tail(x, m);
x++;
- x->rx_buf = &ts->tc.y;
+ x->rx_buf = &packet->tc.y;
x->len = 2;
spi_message_add_tail(x, m);
- m->complete = ads7846_debounce;
+ /* the first sample after switching drivers can be low quality;
+ * optionally discard it, using a second one after the signals
+ * have had enough time to stabilize.
+ */
+ if (pdata->settle_delay_usecs) {
+ x->delay_usecs = pdata->settle_delay_usecs;
+
+ x++;
+ x->tx_buf = &packet->read_y;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.y;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+ }
+
+ m->complete = ads7846_rx_val;
m->context = ts;
m++;
/* turn y- off, x+ on, then leave in lowpower */
x++;
- ts->read_x = READ_X;
- x->tx_buf = &ts->read_x;
+ packet->read_x = READ_X(vref);
+ x->tx_buf = &packet->read_x;
x->len = 1;
spi_message_add_tail(x, m);
x++;
- x->rx_buf = &ts->tc.x;
+ x->rx_buf = &packet->tc.x;
x->len = 2;
spi_message_add_tail(x, m);
- m->complete = ads7846_debounce;
+ /* ... maybe discard first sample ... */
+ if (pdata->settle_delay_usecs) {
+ x->delay_usecs = pdata->settle_delay_usecs;
+
+ x++;
+ x->tx_buf = &packet->read_x;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.x;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+ }
+
+ m->complete = ads7846_rx_val;
m->context = ts;
/* turn y+ off, x- on; we'll use formula #2 */
spi_message_init(m);
x++;
- ts->read_z1 = READ_Z1;
- x->tx_buf = &ts->read_z1;
+ packet->read_z1 = READ_Z1(vref);
+ x->tx_buf = &packet->read_z1;
x->len = 1;
spi_message_add_tail(x, m);
x++;
- x->rx_buf = &ts->tc.z1;
+ x->rx_buf = &packet->tc.z1;
x->len = 2;
spi_message_add_tail(x, m);
- m->complete = ads7846_debounce;
+ /* ... maybe discard first sample ... */
+ if (pdata->settle_delay_usecs) {
+ x->delay_usecs = pdata->settle_delay_usecs;
+
+ x++;
+ x->tx_buf = &packet->read_z1;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.z1;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+ }
+
+ m->complete = ads7846_rx_val;
m->context = ts;
m++;
spi_message_init(m);
x++;
- ts->read_z2 = READ_Z2;
- x->tx_buf = &ts->read_z2;
+ packet->read_z2 = READ_Z2(vref);
+ x->tx_buf = &packet->read_z2;
x->len = 1;
spi_message_add_tail(x, m);
x++;
- x->rx_buf = &ts->tc.z2;
+ x->rx_buf = &packet->tc.z2;
x->len = 2;
spi_message_add_tail(x, m);
- m->complete = ads7846_debounce;
+ /* ... maybe discard first sample ... */
+ if (pdata->settle_delay_usecs) {
+ x->delay_usecs = pdata->settle_delay_usecs;
+
+ x++;
+ x->tx_buf = &packet->read_z2;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.z2;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+ }
+
+ m->complete = ads7846_rx_val;
m->context = ts;
}
spi_message_init(m);
x++;
- ts->pwrdown = PWRDOWN;
- x->tx_buf = &ts->pwrdown;
+ packet->pwrdown = PWRDOWN;
+ x->tx_buf = &packet->pwrdown;
x->len = 1;
spi_message_add_tail(x, m);
x++;
- x->rx_buf = &ts->dummy;
+ x->rx_buf = &packet->dummy;
x->len = 2;
CS_CHANGE(*x);
spi_message_add_tail(x, m);
ts->last_msg = m;
+ ts->reg = regulator_get(&spi->dev, "vcc");
+ if (IS_ERR(ts->reg)) {
+ err = PTR_ERR(ts->reg);
+ dev_err(&spi->dev, "unable to get regulator: %ld\n", err);
+ goto err_free_gpio;
+ }
+
+ err = regulator_enable(ts->reg);
+ if (err) {
+ dev_err(&spi->dev, "unable to enable regulator: %d\n", err);
+ goto err_put_regulator;
+ }
+
if (request_irq(spi->irq, ads7846_irq, IRQF_TRIGGER_FALLING,
spi->dev.driver->name, ts)) {
- dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
- err = -EBUSY;
- goto err_free_mem;
+ dev_info(&spi->dev,
+ "trying pin change workaround on irq %d\n", spi->irq);
+ err = request_irq(spi->irq, ads7846_irq,
+ IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+ spi->dev.driver->name, ts);
+ if (err) {
+ dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
+ goto err_disable_regulator;
+ }
}
+ err = ads784x_hwmon_register(spi, ts);
+ if (err)
+ goto err_free_irq;
+
dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq);
- /* take a first sample, leaving nPENIRQ active; avoid
+ /* take a first sample, leaving nPENIRQ active and vREF off; avoid
* the touchscreen, in case it's not connected.
*/
(void) ads7846_read12_ser(&spi->dev,
READ_12BIT_SER(vaux) | ADS_PD10_ALL_ON);
- /* ads7843/7845 don't have temperature sensors, and
- * use the other sensors a bit differently too
- */
- if (ts->model == 7846) {
- device_create_file(&spi->dev, &dev_attr_temp0);
- device_create_file(&spi->dev, &dev_attr_temp1);
- }
- if (ts->model != 7845)
- device_create_file(&spi->dev, &dev_attr_vbatt);
- device_create_file(&spi->dev, &dev_attr_vaux);
-
- device_create_file(&spi->dev, &dev_attr_pen_down);
-
- device_create_file(&spi->dev, &dev_attr_disable);
+ err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group);
+ if (err)
+ goto err_remove_hwmon;
err = input_register_device(input_dev);
if (err)
- goto err_remove_attr;
+ goto err_remove_attr_group;
- return 0;
+ device_init_wakeup(&spi->dev, pdata->wakeup);
- err_remove_attr:
- device_remove_file(&spi->dev, &dev_attr_disable);
- device_remove_file(&spi->dev, &dev_attr_pen_down);
- if (ts->model == 7846) {
- device_remove_file(&spi->dev, &dev_attr_temp1);
- device_remove_file(&spi->dev, &dev_attr_temp0);
- }
- if (ts->model != 7845)
- device_remove_file(&spi->dev, &dev_attr_vbatt);
- device_remove_file(&spi->dev, &dev_attr_vaux);
+ return 0;
+ err_remove_attr_group:
+ sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group);
+ err_remove_hwmon:
+ ads784x_hwmon_unregister(spi, ts);
+ err_free_irq:
free_irq(spi->irq, ts);
+ err_disable_regulator:
+ regulator_disable(ts->reg);
+ err_put_regulator:
+ regulator_put(ts->reg);
+ err_free_gpio:
+ if (ts->gpio_pendown != -1)
+ gpio_free(ts->gpio_pendown);
+ err_cleanup_filter:
+ if (ts->filter_cleanup)
+ ts->filter_cleanup(ts->filter_data);
err_free_mem:
input_free_device(input_dev);
+ kfree(packet);
kfree(ts);
return err;
}
{
struct ads7846 *ts = dev_get_drvdata(&spi->dev);
+ device_init_wakeup(&spi->dev, false);
+
+ ads784x_hwmon_unregister(spi, ts);
input_unregister_device(ts->input);
ads7846_suspend(spi, PMSG_SUSPEND);
- device_remove_file(&spi->dev, &dev_attr_disable);
- device_remove_file(&spi->dev, &dev_attr_pen_down);
- if (ts->model == 7846) {
- device_remove_file(&spi->dev, &dev_attr_temp1);
- device_remove_file(&spi->dev, &dev_attr_temp0);
- }
- if (ts->model != 7845)
- device_remove_file(&spi->dev, &dev_attr_vbatt);
- device_remove_file(&spi->dev, &dev_attr_vaux);
+ sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group);
free_irq(ts->spi->irq, ts);
/* suspend left the IRQ disabled */
enable_irq(ts->spi->irq);
+ regulator_disable(ts->reg);
+ regulator_put(ts->reg);
+
+ if (ts->gpio_pendown != -1)
+ gpio_free(ts->gpio_pendown);
+
+ if (ts->filter_cleanup)
+ ts->filter_cleanup(ts->filter_data);
+
+ kfree(ts->packet);
kfree(ts);
dev_dbg(&spi->dev, "unregistered touchscreen\n");
static int __init ads7846_init(void)
{
- /* grr, board-specific init should stay out of drivers!! */
-
-#ifdef CONFIG_ARCH_OMAP
- if (machine_is_omap_osk()) {
- /* GPIO4 = PENIRQ; GPIO6 = BUSY */
- omap_request_gpio(4);
- omap_set_gpio_direction(4, 1);
- omap_request_gpio(6);
- omap_set_gpio_direction(6, 1);
- }
- // also TI 1510 Innovator, bitbanging through FPGA
- // also Nokia 770
- // also Palm Tungsten T2
-#endif
-
- // PXA:
- // also Dell Axim X50
- // also HP iPaq H191x/H192x/H415x/H435x
- // also Intel Lubbock (additional to UCB1400; as temperature sensor)
- // also Sharp Zaurus C7xx, C8xx (corgi/sheperd/husky)
-
- // Atmel at91sam9261-EK uses ads7843
-
- // also various AMD Au1x00 devel boards
-
return spi_register_driver(&ads7846_driver);
}
module_init(ads7846_init);
static void __exit ads7846_exit(void)
{
spi_unregister_driver(&ads7846_driver);
-
-#ifdef CONFIG_ARCH_OMAP
- if (machine_is_omap_osk()) {
- omap_free_gpio(4);
- omap_free_gpio(6);
- }
-#endif
-
}
module_exit(ads7846_exit);
MODULE_DESCRIPTION("ADS7846 TouchScreen Driver");
MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:ads7846");
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff