Input: ad714x - use DMA-safe buffers for spi_write()

spi_write() requires use of DMA-safe (cacheline aligned) buffers.
Also use the same buffers when reading data since to avoid extra
locking and potential memory allocation in spi_write_then_read().

Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 31 insertions, 2 deletions

diff --git a/drivers/input/misc/ad714x.h b/drivers/input/misc/ad714x.h
index 45c54fb13f07..d12d14911fc3 100644
--- a/drivers/input/misc/ad714x.h
+++ b/drivers/input/misc/ad714x.h
@@ -11,11 +11,40 @@
 
 #include <linux/types.h>
 
+#define STAGE_NUM              12
+
 struct device;
+struct ad714x_platform_data;
+struct ad714x_driver_data;
 struct ad714x_chip;
 
-typedef int (*ad714x_read_t)(struct device *, unsigned short, unsigned short *);
-typedef int (*ad714x_write_t)(struct device *, unsigned short, unsigned short);
+typedef int (*ad714x_read_t)(struct ad714x_chip *, unsigned short, unsigned short *);
+typedef int (*ad714x_write_t)(struct ad714x_chip *, unsigned short, unsigned short);
+
+struct ad714x_chip {
+        unsigned short h_state;
+        unsigned short l_state;
+        unsigned short c_state;
+        unsigned short adc_reg[STAGE_NUM];
+        unsigned short amb_reg[STAGE_NUM];
+        unsigned short sensor_val[STAGE_NUM];
+
+        struct ad714x_platform_data *hw;
+        struct ad714x_driver_data *sw;
+
+        int irq;
+        struct device *dev;
+        ad714x_read_t read;
+        ad714x_write_t write;
+
+        struct mutex mutex;
+
+        unsigned product;
+        unsigned version;
+
+        __be16 xfer_buf[16] ____cacheline_aligned;
+
+};
 
 int ad714x_disable(struct ad714x_chip *ad714x);
 int ad714x_enable(struct ad714x_chip *ad714x);