Re: [PATCH v2 1/7] Input: synaptics-rmi4 - add support for F03

[Dmitry Torokhov]

Hi Benjamin,

On Fri, Dec 02, 2016 at 12:41:50PM +0100, Benjamin Tissoires wrote:
> From: Lyude Paul <thatslyude@xxxxxxxxx>
> 
> This adds basic functionality for PS/2 passthrough on Synaptics
> Touchpads using RMI4 through smbus.
> 
> Reviewed-by: Andrew Duggan <aduggan@xxxxxxxxxxxxx>
> Signed-off-by: Lyude Paul <thatslyude@xxxxxxxxx>
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
> 
> ---
> 
> changes in v2:
> - amended according to Dmitry's suggestions
> - add a depend on SERIO in the Kconfig
> ---
>  drivers/input/rmi4/Kconfig      |   9 ++
>  drivers/input/rmi4/Makefile     |   1 +
>  drivers/input/rmi4/rmi_bus.c    |   3 +
>  drivers/input/rmi4/rmi_driver.h |   1 +
>  drivers/input/rmi4/rmi_f03.c    | 233 ++++++++++++++++++++++++++++++++++++++++
>  5 files changed, 247 insertions(+)
>  create mode 100644 drivers/input/rmi4/rmi_f03.c
> 
> diff --git a/drivers/input/rmi4/Kconfig b/drivers/input/rmi4/Kconfig
> index a9c36a5..30cc627 100644
> --- a/drivers/input/rmi4/Kconfig
> +++ b/drivers/input/rmi4/Kconfig
> @@ -39,6 +39,15 @@ config RMI4_SMB
>  	  To compile this driver as a module, choose M here: the module will be
>  	  called rmi_smbus.
>  
> +config RMI4_F03
> +        bool "RMI4 Function 03 (PS2 Guest)"
> +        depends on RMI4_CORE && SERIO
> +        help
> +          Say Y here if you want to add support for RMI4 function 03.
> +
> +          Function 03 provides PS2 guest support for RMI4 devices. This
> +          includes support for TrackPoints on TouchPads.
> +
>  config RMI4_2D_SENSOR
>  	bool
>  	depends on RMI4_CORE
> diff --git a/drivers/input/rmi4/Makefile b/drivers/input/rmi4/Makefile
> index e7f4ca6..a199cbe 100644
> --- a/drivers/input/rmi4/Makefile
> +++ b/drivers/input/rmi4/Makefile
> @@ -4,6 +4,7 @@ rmi_core-y := rmi_bus.o rmi_driver.o rmi_f01.o
>  rmi_core-$(CONFIG_RMI4_2D_SENSOR) += rmi_2d_sensor.o
>  
>  # Function drivers
> +rmi_core-$(CONFIG_RMI4_F03) += rmi_f03.o
>  rmi_core-$(CONFIG_RMI4_F11) += rmi_f11.o
>  rmi_core-$(CONFIG_RMI4_F12) += rmi_f12.o
>  rmi_core-$(CONFIG_RMI4_F30) += rmi_f30.o
> diff --git a/drivers/input/rmi4/rmi_bus.c b/drivers/input/rmi4/rmi_bus.c
> index 81be9c1..1c40d94 100644
> --- a/drivers/input/rmi4/rmi_bus.c
> +++ b/drivers/input/rmi4/rmi_bus.c
> @@ -305,6 +305,9 @@ struct bus_type rmi_bus_type = {
>  
>  static struct rmi_function_handler *fn_handlers[] = {
>  	&rmi_f01_handler,
> +#ifdef CONFIG_RMI4_F03
> +	&rmi_f03_handler,
> +#endif
>  #ifdef CONFIG_RMI4_F11
>  	&rmi_f11_handler,
>  #endif
> diff --git a/drivers/input/rmi4/rmi_driver.h b/drivers/input/rmi4/rmi_driver.h
> index cc94585..24f8f76 100644
> --- a/drivers/input/rmi4/rmi_driver.h
> +++ b/drivers/input/rmi4/rmi_driver.h
> @@ -121,6 +121,7 @@ static inline void rmi_f34_remove_sysfs(struct rmi_device *rmi_dev)
>  #endif /* CONFIG_RMI_F34 */
>  
>  extern struct rmi_function_handler rmi_f01_handler;
> +extern struct rmi_function_handler rmi_f03_handler;
>  extern struct rmi_function_handler rmi_f11_handler;
>  extern struct rmi_function_handler rmi_f12_handler;
>  extern struct rmi_function_handler rmi_f30_handler;
> diff --git a/drivers/input/rmi4/rmi_f03.c b/drivers/input/rmi4/rmi_f03.c
> new file mode 100644
> index 0000000..fd8f6e5
> --- /dev/null
> +++ b/drivers/input/rmi4/rmi_f03.c
> @@ -0,0 +1,233 @@
> +/*
> + * Copyright (C) 2015-2016 Red Hat
> + * Copyright (C) 2015 Lyude Paul <thatslyude@xxxxxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License version 2 as published by
> + * the Free Software Foundation.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/slab.h>
> +#include <linux/serio.h>
> +#include <linux/notifier.h>
> +#include "rmi_driver.h"
> +
> +#define RMI_F03_RX_DATA_OFB		0x01
> +#define RMI_F03_OB_SIZE			2
> +
> +#define RMI_F03_OB_OFFSET		2
> +#define RMI_F03_OB_DATA_OFFSET		1
> +#define RMI_F03_OB_FLAG_TIMEOUT		BIT(6)
> +#define RMI_F03_OB_FLAG_PARITY		BIT(7)
> +
> +#define RMI_F03_DEVICE_COUNT		0x07
> +#define RMI_F03_BYTES_PER_DEVICE_MASK	0x70
> +#define RMI_F03_BYTES_PER_DEVICE_SHIFT	4
> +#define RMI_F03_QUEUE_LENGTH		0x0F
> +
> +struct f03_data {
> +	struct rmi_function *fn;
> +
> +	struct serio *serio;
> +
> +	u8 device_count;
> +	u8 rx_queue_length;
> +};
> +
> +static int rmi_f03_pt_write(struct serio *id, unsigned char val)
> +{
> +	struct f03_data *f03 = id->port_data;
> +	int error;
> +
> +	rmi_dbg(RMI_DEBUG_FN, &f03->fn->dev,
> +		"%s: Wrote %.2hhx to PS/2 passthrough address",
> +		__func__, val);
> +
> +	error = rmi_write(f03->fn->rmi_dev, f03->fn->fd.data_base_addr, val);
> +	if (error) {
> +		dev_err(&f03->fn->dev,
> +			"%s: Failed to write to F03 TX register (%d).\n",
> +			__func__, error);
> +		return error;
> +	}
> +
> +	return 0;
> +}
> +
> +static int rmi_f03_initialize(struct f03_data *f03)
> +{
> +	struct rmi_function *fn = f03->fn;
> +	struct device *dev = &fn->dev;
> +	int error;
> +	u8 bytes_per_device;
> +	u8 query1;
> +	size_t query2_len;
> +
> +	error = rmi_read(fn->rmi_dev, fn->fd.query_base_addr, &query1);
> +	if (error) {
> +		dev_err(dev, "Failed to read query register (%d).\n", error);
> +		return error;
> +	}
> +
> +	f03->device_count = query1 & RMI_F03_DEVICE_COUNT;
> +	bytes_per_device = (query1 & RMI_F03_BYTES_PER_DEVICE_MASK) >>
> +		RMI_F03_BYTES_PER_DEVICE_SHIFT;
> +
> +	query2_len = f03->device_count * bytes_per_device;
> +
> +	/*
> +	 * The first generation of image sensors don't have a second part to
> +	 * their f03 query, as such we have to set some of these values manually
> +	 */
> +	if (query2_len < 1) {
> +		f03->device_count = 1;
> +		f03->rx_queue_length = 7;
> +	} else {
> +		u8 query2[query2_len];

sparse does not like variable length arrays too much, I changed this
(and one below) to a static length array, and applied.

Thanks.

-- 
Dmitry