[PATCH v2 05/21] ARM: pxa: magician: Add support for ADS7846 touchscreen

Petr Cvek
2015-08-17T21:56:04Z

Add support for ADS7846 touchscreen.

Signed-off-by: Petr Cvek <petr.cvek@tul.cz>
---
arch/arm/mach-pxa/magician.c | 86 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 86 insertions(+)

diff --git a/arch/arm/mach-pxa/magician.c b/arch/arm/mach-pxa/magician.c
index bc206f8..fc1c035 100644
--- a/arch/arm/mach-pxa/magician.c
+++ b/arch/arm/mach-pxa/magician.c
@@ -68,6 +68,7 @@
#include <linux/pwm_backlight.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/gpio-regulator.h>
+#include <linux/regulator/fixed.h>
#include <linux/regulator/machine.h>
#include <linux/usb/gpio_vbus.h>
#include <linux/i2c/pxa-i2c.h>
@@ -84,6 +85,10 @@
#include <linux/platform_data/irda-pxaficp.h>
#include <linux/platform_data/usb-ohci-pxa27x.h>

+#include <linux/spi/spi.h>
+#include <linux/spi/pxa2xx_spi.h>
+#include <linux/spi/ads7846.h>
+
#include "devices.h"
#include "generic.h"

@@ -766,6 +771,37 @@ 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,
+ },
+};
+
+/*
* MMC/SD
*/

@@ -841,6 +877,51 @@ static struct i2c_pxa_platform_data i2c_info = {
};

/*
+ * Touchscreen
+ */
+
+static struct ads7846_platform_data ads7846_pdata = {
+ .model = 7846,
+ .x_min = 0,
+ .y_min = 0,
+ .x_max = 4096,
+ .y_max = 4096,
+ .x_plate_ohms = 320, /* measured */
+ .y_plate_ohms = 500,
+ .pressure_max = 255, /* up to 12bit sampling */
+ .debounce_max = 10,
+ .debounce_tol = 3,
+ .debounce_rep = 1,
+ .gpio_pendown = GPIO115_MAGICIAN_nPEN_IRQ,
+ .keep_vref_on = 1, /* FIXME, external Vref? */
+ .vref_delay_usecs = 100,
+ /* .wait_for_sync, GPIO77_LCD_BIAS low noise measure, latency! */
+};
+
+struct pxa2xx_spi_chip tsc2046_chip_info = {
+ .tx_threshold = 1,
+ .rx_threshold = 2,
+ .timeout = 64,
+ .gpio_cs = -1,
+};
+
+static struct pxa2xx_spi_master magician_spi_info = {
+ .num_chipselect = 1,
+/* .enable_dma = 1, */ /* FIXME probably unnecessary */
+};
+
+static struct spi_board_info ads7846_spi_board_info[] __initdata = {
+ {
+ .modalias = "ads7846",
+ .bus_num = 2,
+ .max_speed_hz = 1857143,
+ .platform_data = &ads7846_pdata,
+ .controller_data = &tsc2046_chip_info,
+ .irq = PXA_GPIO_TO_IRQ(GPIO115_MAGICIAN_nPEN_IRQ),
+ },
+};
+
+/*
* Platform devices
*/

@@ -849,6 +930,7 @@ static struct platform_device *devices[] __initdata = {
&egpio,
&pwm_backlight,
&pasic3,
+ &vads7846_device,
&bq24022,
&gpio_vbus,
&power_supply,
@@ -915,6 +997,10 @@ static void __init magician_init(void)
lcd_select ? &samsung_info : &toppoly_info);
} 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));
+
}

MACHINE_START(MAGICIAN, "HTC Magician")
--
1.7.12.1