@@ -24,6 +24,7 @@
#define GPIO10_MAGICIAN_GSM_IRQ 10
#define GPIO11_MAGICIAN_GSM_OUT1 11
#define GPIO13_MAGICIAN_CPLD_IRQ 13
+#define GPIO14_MAGICIAN_TSC2046_CS 14
#define GPIO18_MAGICIAN_UNKNOWN 18
#define GPIO22_MAGICIAN_VIBRA_EN 22
#define GPIO26_MAGICIAN_GSM_POWER 26
@@ -54,6 +54,10 @@
#include "devices.h"
#include "generic.h"
+#include <linux/spi/spi.h>
+#include <linux/spi/pxa2xx_spi.h>
+#include <linux/spi/ads7846.h>
+
static unsigned long magician_pin_config[] __initdata = {
/* SDRAM and Static Memory I/O Signals */
@@ -85,7 +89,7 @@ static unsigned long magician_pin_config[] __initdata = {
/* SSP 2 TSC2046 touchscreen */
GPIO19_SSP2_SCLK,
- GPIO14_SSP2_SFRM,
+ MFP_CFG_OUT(GPIO14, AF0, DRIVE_HIGH), /* frame as GPIO */
GPIO89_SSP2_TXD,
GPIO88_SSP2_RXD,
@@ -675,6 +679,37 @@ static struct platform_device bq24022 = {
};
/*
+ * fixed regulator for ads7846
+ */
+
+static struct regulator_consumer_supply ads7846_supply =
+ REGULATOR_SUPPLY("vcc", "spi2.0");
+
+static struct regulator_init_data vads7846_regulator = {
+ .constraints = {
+ .valid_ops_mask = REGULATOR_CHANGE_STATUS,
+ },
+ .num_consumer_supplies = 1,
+ .consumer_supplies = &ads7846_supply,
+};
+
+static struct fixed_voltage_config vads7846 = {
+ .supply_name = "vads7846",
+ .microvolts = 3300000, /* probably */
+ .gpio = -EINVAL,
+ .startup_delay = 0,
+ .init_data = &vads7846_regulator,
+};
+
+static struct platform_device vads7846_device = {
+ .name = "reg-fixed-voltage",
+ .id = -1,
+ .dev = {
+ .platform_data = &vads7846,
+ },
+};
+
+/*
* Vcore regulator MAX1587A
*/
@@ -852,6 +887,49 @@ static struct i2c_pxa_platform_data magician_i2c_power_info = {
};
/*
+ * Touchscreen
+ */
+
+static struct ads7846_platform_data ads7846_pdata = {
+ .model = 7846,
+ .x_plate_ohms = 317,
+ .y_plate_ohms = 500,
+ .pressure_max = 1023, /* with x plate ohms it will overflow 255 */
+ .debounce_max = 3, /* first readout is always bad */
+ .debounce_tol = 30,
+ .debounce_rep = 0,
+ .gpio_pendown = GPIO115_MAGICIAN_nPEN_IRQ,
+ .keep_vref_on = 1,
+ .wakeup = true,
+ .vref_delay_usecs = 100,
+ .penirq_recheck_delay_usecs = 100,
+};
+
+struct pxa2xx_spi_chip tsc2046_chip_info = {
+ .tx_threshold = 1,
+ .rx_threshold = 2,
+ .timeout = 64,
+ /* NOTICE must be GPIO, incompatibility with hw PXA SPI framing */
+ .gpio_cs = GPIO14_MAGICIAN_TSC2046_CS,
+};
+
+static struct pxa2xx_spi_master magician_spi_info = {
+ .num_chipselect = 1,
+ .enable_dma = 1,
+};
+
+static struct spi_board_info ads7846_spi_board_info[] __initdata = {
+ {
+ .modalias = "ads7846",
+ .bus_num = 2,
+ .max_speed_hz = 2500000,
+ .platform_data = &ads7846_pdata,
+ .controller_data = &tsc2046_chip_info,
+ .irq = PXA_GPIO_TO_IRQ(GPIO115_MAGICIAN_nPEN_IRQ),
+ },
+};
+
+/*
* Platform devices
*/
@@ -865,6 +943,7 @@ static struct platform_device *devices[] __initdata = {
&power_supply,
&strataflash,
&leds_gpio,
+ &vads7846_device,
};
static struct gpio magician_global_gpios[] = {
@@ -922,6 +1001,9 @@ static void __init magician_init(void)
} else
pr_err("LCD detection: CPLD mapping failed\n");
+ pxa2xx_set_spi_info(2, &magician_spi_info);
+ spi_register_board_info(ARRAY_AND_SIZE(ads7846_spi_board_info));
+
regulator_register_always_on(0, "power", pwm_backlight_supply,
ARRAY_SIZE(pwm_backlight_supply), 5000000);
This patch adds a support for ADS7846 touchscreen driver. The basic functionality was tested, x_plate_ohms and y_plate_ohms were physically measured. The value pressure_max was empirically set to match the measured range, which is affected by x_plate_ohms and ADS samples. The value of keep_vref_on should be set. A tested model (T-Mobile MDA Compact PM10A) doesn't seem to use Vref pin as the input from an external source. On this model the unset keep_vref_on cause high jitter of measured values. SPI framing pin (gpio_cs) must be used in GPIO mode due to an incompatible autoframing of PXA27x controller and ADS7846 device. Signed-off-by: Petr Cvek <petr.cvek@tul.cz> --- arch/arm/mach-pxa/include/mach/magician.h | 1 + arch/arm/mach-pxa/magician.c | 84 ++++++++++++++++++++++++++++++- 2 files changed, 84 insertions(+), 1 deletion(-)