diff options
| author | David Brownell <david-b@pacbell.net> | 2008-04-02 00:43:01 -0400 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2008-04-02 00:43:01 -0400 |
| commit | 7c6d0ee14cb7a4cfad4864dc196256da5749bc0c (patch) | |
| tree | a24af9205d80605d6e4b01693b652f9837071e5c | |
| parent | e6cdd15629a5a99d805fa3cbf0f5174bcfc685bb (diff) | |
Input: ads7846 - simplify support of external vREF (and ads7843)
This updates the ads7846 driver to handle external vREF (required
on boards using ads7843 chips) without module parameters, and also
removes a needless variable with its associated bogus gcc warning.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
| -rw-r--r-- | drivers/input/touchscreen/ads7846.c | 22 | ||||
| -rw-r--r-- | include/linux/spi/ads7846.h | 3 |
2 files changed, 12 insertions, 13 deletions
diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c index 57a1c28bf12..a571aa965da 100644 --- a/drivers/input/touchscreen/ads7846.c +++ b/drivers/input/touchscreen/ads7846.c @@ -87,6 +87,7 @@ struct ads7846 { #endif u16 model; + u16 vref_mv; u16 vref_delay_usecs; u16 x_plate_ohms; u16 pressure_max; @@ -184,9 +185,6 @@ struct ads7846 { * The range is GND..vREF. The ads7843 and ads7835 must use external vREF; * ads7846 lets that pin be unconnected, to use internal vREF. */ -static unsigned vREF_mV; -module_param(vREF_mV, uint, 0); -MODULE_PARM_DESC(vREF_mV, "external vREF voltage, in milliVolts"); struct ser_req { u8 ref_on; @@ -213,7 +211,6 @@ static int ads7846_read12_ser(struct device *dev, unsigned command) struct ads7846 *ts = dev_get_drvdata(dev); struct ser_req *req = kzalloc(sizeof *req, GFP_KERNEL); int status; - int uninitialized_var(sample); int use_internal; if (!req) @@ -270,13 +267,13 @@ static int ads7846_read12_ser(struct device *dev, unsigned command) if (status == 0) { /* on-wire is a must-ignore bit, a BE12 value, then padding */ - sample = be16_to_cpu(req->sample); - sample = sample >> 3; - sample &= 0x0fff; + status = be16_to_cpu(req->sample); + status = status >> 3; + status &= 0x0fff; } kfree(req); - return status ? status : sample; + return status; } #if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE) @@ -317,7 +314,7 @@ static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v) unsigned retval = v; /* external resistors may scale vAUX into 0..vREF */ - retval *= vREF_mV; + retval *= ts->vref_mv; retval = retval >> 12; return retval; } @@ -375,14 +372,14 @@ static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts) /* hwmon sensors need a reference voltage */ switch (ts->model) { case 7846: - if (!vREF_mV) { + if (!ts->vref_mv) { dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n"); - vREF_mV = 2500; + ts->vref_mv = 2500; } break; case 7845: case 7843: - if (!vREF_mV) { + if (!ts->vref_mv) { dev_warn(&spi->dev, "external vREF for ADS%d not specified\n", ts->model); @@ -875,6 +872,7 @@ static int __devinit ads7846_probe(struct spi_device *spi) ts->spi = spi; ts->input = input_dev; + ts->vref_mv = pdata->vref_mv; hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); ts->timer.function = ads7846_timer; diff --git a/include/linux/spi/ads7846.h b/include/linux/spi/ads7846.h index 334d3141162..daf744017a3 100644 --- a/include/linux/spi/ads7846.h +++ b/include/linux/spi/ads7846.h @@ -14,7 +14,8 @@ enum ads7846_filter { struct ads7846_platform_data { u16 model; /* 7843, 7845, 7846. */ u16 vref_delay_usecs; /* 0 for external vref; etc */ - int keep_vref_on:1; /* set to keep vref on for differential + u16 vref_mv; /* external vref value, milliVolts */ + bool keep_vref_on; /* set to keep vref on for differential * measurements as well */ /* Settling time of the analog signals; a function of Vcc and the |