Input: synaptics-rmi4 - propagate correct number of rx and tx electrodes to F54

F54 diagnostics report functions provide data based on the number of
enabled rx and tx electrodes, which is not identical to the number of
electrodes reported with F54:Query0 and F54:Query1. Those values report
the number of supported electrodes, not the number of enabled electrodes.
The number of enabled electrodes can be determined by analyzing F55:Ctrl1
(sensor receiver assignment) and F55:Ctrl2 (sensor transmitter assignment).

Propagate the number of enabled electrodes from F55 to F54 to avoid
corrupted output if not all electrodes are enabled.

Fixes: 3a762dbd ("[media] Input: synaptics-rmi4 - add support for F54 ...")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Nick Dyer <nick@shmanahar.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/rmi4/Kconfig

@@ -90,6 +90,7 @@ config RMI4_F54
 	depends on RMI4_CORE
 	depends on VIDEO_V4L2=y || (RMI4_CORE=m && VIDEO_V4L2=m)
 	select VIDEOBUF2_VMALLOC
+	select RMI4_F55
 	help
 	  Say Y here if you want to add support for RMI4 function 54
 

drivers/input/rmi4/rmi_f54.c

@@ -217,8 +217,10 @@ static int rmi_f54_request_report(struct rmi_function *fn, u8 report_type)
 
 static size_t rmi_f54_get_report_size(struct f54_data *f54)
 {
-	u8 rx = f54->num_rx_electrodes ? : f54->num_rx_electrodes;
-	u8 tx = f54->num_tx_electrodes ? : f54->num_tx_electrodes;
+	struct rmi_device *rmi_dev = f54->fn->rmi_dev;
+	struct rmi_driver_data *drv_data = dev_get_drvdata(&rmi_dev->dev);
+	u8 rx = drv_data->num_rx_electrodes ? : f54->num_rx_electrodes;
+	u8 tx = drv_data->num_tx_electrodes ? : f54->num_tx_electrodes;
 	size_t size;
 
 	switch (rmi_f54_get_reptype(f54, f54->input)) {
@@ -402,6 +404,10 @@ static int rmi_f54_vidioc_enum_input(struct file *file, void *priv,
 
 static int rmi_f54_set_input(struct f54_data *f54, unsigned int i)
 {
+	struct rmi_device *rmi_dev = f54->fn->rmi_dev;
+	struct rmi_driver_data *drv_data = dev_get_drvdata(&rmi_dev->dev);
+	u8 rx = drv_data->num_rx_electrodes ? : f54->num_rx_electrodes;
+	u8 tx = drv_data->num_tx_electrodes ? : f54->num_tx_electrodes;
 	struct v4l2_pix_format *f = &f54->format;
 	enum rmi_f54_report_type reptype;
 	int ret;
@@ -416,8 +422,8 @@ static int rmi_f54_set_input(struct f54_data *f54, unsigned int i)
 
 	f54->input = i;
 
-	f->width = f54->num_rx_electrodes;
-	f->height = f54->num_tx_electrodes;
+	f->width = rx;
+	f->height = tx;
 	f->field = V4L2_FIELD_NONE;
 	f->colorspace = V4L2_COLORSPACE_RAW;
 	f->bytesperline = f->width * sizeof(u16);

drivers/input/rmi4/rmi_f55.c

@@ -38,6 +38,8 @@ struct f55_data {
 
 static int rmi_f55_detect(struct rmi_function *fn)
 {
+	struct rmi_device *rmi_dev = fn->rmi_dev;
+	struct rmi_driver_data *drv_data = dev_get_drvdata(&rmi_dev->dev);
 	struct f55_data *f55;
 	int error;
 
@@ -57,6 +59,9 @@ static int rmi_f55_detect(struct rmi_function *fn)
 	f55->cfg_num_rx_electrodes = f55->num_rx_electrodes;
 	f55->cfg_num_tx_electrodes = f55->num_rx_electrodes;
 
+	drv_data->num_rx_electrodes = f55->cfg_num_rx_electrodes;
+	drv_data->num_tx_electrodes = f55->cfg_num_rx_electrodes;
+
 	if (f55->qry[F55_PHYS_CHAR_OFFSET] & F55_CAP_SENSOR_ASSIGN) {
 		int i, total;
 		u8 buf[256];
@@ -78,6 +83,7 @@ static int rmi_f55_detect(struct rmi_function *fn)
 					total++;
 			}
 			f55->cfg_num_rx_electrodes = total;
+			drv_data->num_rx_electrodes = total;
 		}
 
 		error = rmi_read_block(fn->rmi_dev,
@@ -90,6 +96,7 @@ static int rmi_f55_detect(struct rmi_function *fn)
 					total++;
 			}
 			f55->cfg_num_tx_electrodes = total;
+			drv_data->num_tx_electrodes = total;
 		}
 	}
 

include/linux/rmi.h

@@ -354,6 +354,9 @@ struct rmi_driver_data {
 	u8 pdt_props;
 	u8 bsr;
 
+	u8 num_rx_electrodes;
+	u8 num_tx_electrodes;
+
 	bool enabled;
 
 	void *data;