Input: add AD7879 Touchscreen driver

[randy.dunlap@oracle.com: don't use bus_id]
[dtor@mail.ru: locking and other fixups]
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 35 insertions, 0 deletions

diff --git a/include/linux/spi/ad7879.h b/include/linux/spi/ad7879.h
new file mode 100644
index 000000000000..4231104c9afa
--- /dev/null
+++ b/include/linux/spi/ad7879.h
@@ -0,0 +1,35 @@
+/* linux/spi/ad7879.h */
+
+/* Touchscreen characteristics vary between boards and models.  The
+ * platform_data for the device's "struct device" holds this information.
+ *
+ * It's OK if the min/max values are zero.
+ */
+struct ad7879_platform_data {
+        u16     model;                  /* 7879 */
+        u16     x_plate_ohms;
+        u16     x_min, x_max;
+        u16     y_min, y_max;
+        u16     pressure_min, pressure_max;
+
+        /* [0..255] 0=OFF Starts at 1=550us and goes
+         * all the way to 9.440ms in steps of 35us.
+         */
+        u8      pen_down_acc_interval;
+        /* [0..15] Starts at 0=128us and goes all the
+         * way to 4.096ms in steps of 128us.
+         */
+        u8      first_conversion_delay;
+        /* [0..3] 0 = 2us, 1 = 4us, 2 = 8us, 3 = 16us */
+        u8      acquisition_time;
+        /* [0..3] Average X middle samples 0 = 2, 1 = 4, 2 = 8, 3 = 16 */
+        u8      averaging;
+        /* [0..3] Perform X measurements 0 = OFF,
+         * 1 = 4, 2 = 8, 3 = 16 (median > averaging)
+         */
+        u8      median;
+        /* 1 = AUX/VBAT/GPIO set to GPIO Output */
+        u8      gpio_output;
+        /* Initial GPIO pin state (valid if gpio_output = 1) */
+        u8      gpio_default;
+};