Re: [PATCH 2/4] Input: synaptics-rmi4 - rework transport device allocation

[Christopher Heiny]

On 01/09/2014 11:44 PM, Dmitry Torokhov wrote:
> Instead of allocating common and private part of transport device
> separately make private wrap common part and get rid of private data
> pointer in the transport device.
>
> Also rename rmi_i2c_data -> rmi_i2c_xport and data -> rmi_i2c.

Acked-by: Christopher Heiny <cheiny@xxxxxxxxxxxxx>

> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> ---
>   drivers/input/rmi4/rmi_bus.h |   3 --
>   drivers/input/rmi4/rmi_i2c.c | 112 +++++++++++++++++++++----------------------
>   2 files changed, 56 insertions(+), 59 deletions(-)
>
> diff --git a/drivers/input/rmi4/rmi_bus.h b/drivers/input/rmi4/rmi_bus.h
> index ccf26dc..decb479 100644
> --- a/drivers/input/rmi4/rmi_bus.h
> +++ b/drivers/input/rmi4/rmi_bus.h
> @@ -165,7 +165,6 @@ struct rmi_transport_stats {
>    * default irq_thread implementation.
>    * @hard_irq: if not NULL, the sensor driver will use this for the hard IRQ
>    * handling
> - * @data: Private data pointer
>    * @proto_name: name of the transport protocol (SPI, i2c, etc)
>    * @ops: pointer to transport operations implementation
>    * @stats: transport statistics
> @@ -181,8 +180,6 @@ struct rmi_transport_dev {
>   	irqreturn_t (*irq_thread)(int irq, void *p);
>   	irqreturn_t (*hard_irq)(int irq, void *p);
>
> -	void *data;
> -
>   	const char *proto_name;
>   	const struct rmi_transport_ops *ops;
>   	struct rmi_transport_stats stats;
> diff --git a/drivers/input/rmi4/rmi_i2c.c b/drivers/input/rmi4/rmi_i2c.c
> index 40badf3..cdc8527 100644
> --- a/drivers/input/rmi4/rmi_i2c.c
> +++ b/drivers/input/rmi4/rmi_i2c.c
> @@ -17,22 +17,25 @@
>   #define BUFFER_SIZE_INCREMENT 32
>
>   /**
> - * struct rmi_i2c_data - stores information for i2c communication
> + * struct rmi_i2c_xport - stores information for i2c communication
> + *
> + * @xport: The transport interface structure
>    *
>    * @page_mutex: Locks current page to avoid changing pages in unexpected ways.
>    * @page: Keeps track of the current virtual page
> - * @xport: Pointer to the transport interface
>    *
>    * @tx_buf: Buffer used for transmitting data to the sensor over i2c.
>    * @tx_buf_size: Size of the buffer
>    */
> -struct rmi_i2c_data {
> +struct rmi_i2c_xport {
> +	struct rmi_transport_dev xport;
> +	struct i2c_client *client;
> +
>   	struct mutex page_mutex;
>   	int page;
> -	struct rmi_transport_dev *xport;
>
>   	u8 *tx_buf;
> -	int tx_buf_size;
> +	size_t tx_buf_size;
>   };
>
>   #define RMI_PAGE_SELECT_REGISTER 0xff
> @@ -52,10 +55,10 @@ struct rmi_i2c_data {
>    *
>    * Returns zero on success, non-zero on failure.
>    */
> -static int rmi_set_page(struct rmi_transport_dev *xport, u8 page)
> +static int rmi_set_page(struct rmi_i2c_xport *rmi_i2c, u8 page)
>   {
> -	struct i2c_client *client = to_i2c_client(xport->dev);
> -	struct rmi_i2c_data *data = xport->data;
> +	struct rmi_transport_dev *xport = &rmi_i2c->xport;
> +	struct i2c_client *client = rmi_i2c->client;
>   	u8 txbuf[2] = {RMI_PAGE_SELECT_REGISTER, page};
>   	int retval;
>
> @@ -70,37 +73,40 @@ static int rmi_set_page(struct rmi_transport_dev *xport, u8 page)
>   			"%s: set page failed: %d.", __func__, retval);
>   		return (retval < 0) ? retval : -EIO;
>   	}
> -	data->page = page;
> +	rmi_i2c->page = page;
>   	return 0;
>   }
>
>   static int rmi_i2c_write_block(struct rmi_transport_dev *xport, u16 addr,
>   			       const void *buf, size_t len)
>   {
> -	struct i2c_client *client = to_i2c_client(xport->dev);
> -	struct rmi_i2c_data *data = xport->data;
> +	struct rmi_i2c_xport *rmi_i2c =
> +		container_of(xport, struct rmi_i2c_xport, xport);
> +	struct i2c_client *client = rmi_i2c->client;
>   	size_t tx_size = len + 1;
>   	int retval;
>
> -	mutex_lock(&data->page_mutex);
> -
> -	if (!data->tx_buf || data->tx_buf_size < tx_size) {
> -		if (data->tx_buf)
> -			devm_kfree(&client->dev, data->tx_buf);
> -		data->tx_buf_size = tx_size + BUFFER_SIZE_INCREMENT;
> -		data->tx_buf = devm_kzalloc(&client->dev, data->tx_buf_size,
> -					    GFP_KERNEL);
> -		if (!data->tx_buf) {
> -			data->tx_buf_size = 0;
> +	mutex_lock(&rmi_i2c->page_mutex);
> +
> +	if (!rmi_i2c->tx_buf || rmi_i2c->tx_buf_size < tx_size) {
> +		if (rmi_i2c->tx_buf)
> +			devm_kfree(&client->dev, rmi_i2c->tx_buf);
> +		rmi_i2c->tx_buf_size = tx_size + BUFFER_SIZE_INCREMENT;
> +		rmi_i2c->tx_buf = devm_kzalloc(&client->dev,
> +					       rmi_i2c->tx_buf_size,
> +					       GFP_KERNEL);
> +		if (!rmi_i2c->tx_buf) {
> +			rmi_i2c->tx_buf_size = 0;
>   			retval = -ENOMEM;
>   			goto exit;
>   		}
>   	}
> -	data->tx_buf[0] = addr & 0xff;
> -	memcpy(data->tx_buf + 1, buf, len);
>
> -	if (RMI_I2C_PAGE(addr) != data->page) {
> -		retval = rmi_set_page(xport, RMI_I2C_PAGE(addr));
> +	rmi_i2c->tx_buf[0] = addr & 0xff;
> +	memcpy(rmi_i2c->tx_buf + 1, buf, len);
> +
> +	if (RMI_I2C_PAGE(addr) != rmi_i2c->page) {
> +		retval = rmi_set_page(rmi_i2c, RMI_I2C_PAGE(addr));
>   		if (retval < 0)
>   			goto exit;
>   	}
> @@ -110,29 +116,30 @@ static int rmi_i2c_write_block(struct rmi_transport_dev *xport, u16 addr,
>
>   	xport->stats.tx_count++;
>   	xport->stats.tx_bytes += tx_size;
> -	retval = i2c_master_send(client, data->tx_buf, tx_size);
> +	retval = i2c_master_send(client, rmi_i2c->tx_buf, tx_size);
>   	if (retval < 0)
>   		xport->stats.tx_errs++;
>   	else
>   		retval--; /* don't count the address byte */
>
>   exit:
> -	mutex_unlock(&data->page_mutex);
> +	mutex_unlock(&rmi_i2c->page_mutex);
>   	return retval;
>   }
>
>   static int rmi_i2c_read_block(struct rmi_transport_dev *xport, u16 addr,
>   			      void *buf, size_t len)
>   {
> -	struct i2c_client *client = to_i2c_client(xport->dev);
> -	struct rmi_i2c_data *data = xport->data;
> +	struct rmi_i2c_xport *rmi_i2c =
> +		container_of(xport, struct rmi_i2c_xport, xport);
> +	struct i2c_client *client = rmi_i2c->client;
>   	u8 txbuf[1] = {addr & 0xff};
>   	int retval;
>
> -	mutex_lock(&data->page_mutex);
> +	mutex_lock(&rmi_i2c->page_mutex);
>
> -	if (RMI_I2C_PAGE(addr) != data->page) {
> -		retval = rmi_set_page(xport, RMI_I2C_PAGE(addr));
> +	if (RMI_I2C_PAGE(addr) != rmi_i2c->page) {
> +		retval = rmi_set_page(rmi_i2c, RMI_I2C_PAGE(addr));
>   		if (retval < 0)
>   			goto exit;
>   	}
> @@ -160,7 +167,7 @@ static int rmi_i2c_read_block(struct rmi_transport_dev *xport, u16 addr,
>   			len, addr, (int)len, buf);
>
>   exit:
> -	mutex_unlock(&data->page_mutex);
> +	mutex_unlock(&rmi_i2c->page_mutex);
>   	return retval;
>   }
>
> @@ -174,14 +181,14 @@ static int rmi_i2c_probe(struct i2c_client *client,
>   {
>   	const struct rmi_device_platform_data *pdata =
>   				dev_get_platdata(&client->dev);
> -	struct rmi_transport_dev *xport;
> -	struct rmi_i2c_data *data;
> +	struct rmi_i2c_xport *rmi_i2c;
>   	int retval;
>
>   	if (!pdata) {
>   		dev_err(&client->dev, "no platform data\n");
>   		return -EINVAL;
>   	}
> +
>   	dev_dbg(&client->dev, "Probing %s at %#02x (GPIO %d).\n",
>   		pdata->sensor_name ? pdata->sensor_name : "-no name-",
>   		client->addr, pdata->attn_gpio);
> @@ -202,44 +209,36 @@ static int rmi_i2c_probe(struct i2c_client *client,
>   		}
>   	}
>
> -	xport = devm_kzalloc(&client->dev, sizeof(struct rmi_transport_dev),
> +	rmi_i2c = devm_kzalloc(&client->dev, sizeof(struct rmi_i2c_xport),
>   				GFP_KERNEL);
> -
> -	if (!xport)
> +	if (!rmi_i2c)
>   		return -ENOMEM;
>
> -	data = devm_kzalloc(&client->dev, sizeof(struct rmi_i2c_data),
> -				GFP_KERNEL);
> -	if (!data)
> -		return -ENOMEM;
> -
> -	data->xport = xport;
> -
> -	xport->data = data;
> -	xport->dev = &client->dev;
> +	rmi_i2c->client = client;
> +	mutex_init(&rmi_i2c->page_mutex);
>
> -	xport->proto_name = "i2c";
> -	xport->ops = &rmi_i2c_ops;
> -
> -	mutex_init(&data->page_mutex);
> +	rmi_i2c->xport.dev = &client->dev;
> +	rmi_i2c->xport.proto_name = "i2c";
> +	rmi_i2c->xport.ops = &rmi_i2c_ops;
>
>   	/*
>   	 * Setting the page to zero will (a) make sure the PSR is in a
>   	 * known state, and (b) make sure we can talk to the device.
>   	 */
> -	retval = rmi_set_page(xport, 0);
> +	retval = rmi_set_page(rmi_i2c, 0);
>   	if (retval) {
>   		dev_err(&client->dev, "Failed to set page select to 0.\n");
>   		return retval;
>   	}
>
> -	retval = rmi_register_transport_device(xport);
> +	retval = rmi_register_transport_device(&rmi_i2c->xport);
>   	if (retval) {
>   		dev_err(&client->dev, "Failed to register transport driver at 0x%.2X.\n",
>   			client->addr);
>   		goto err_gpio;
>   	}
> -	i2c_set_clientdata(client, xport);
> +
> +	i2c_set_clientdata(client, rmi_i2c);
>
>   	dev_info(&client->dev, "registered rmi i2c driver at %#04x.\n",
>   			client->addr);
> @@ -248,16 +247,17 @@ static int rmi_i2c_probe(struct i2c_client *client,
>   err_gpio:
>   	if (pdata->gpio_config)
>   		pdata->gpio_config(pdata->gpio_data, false);
> +
>   	return retval;
>   }
>
>   static int rmi_i2c_remove(struct i2c_client *client)
>   {
> -	struct rmi_transport_dev *xport = i2c_get_clientdata(client);
>   	const struct rmi_device_platform_data *pdata =
>   				dev_get_platdata(&client->dev);
> +	struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client);
>
> -	rmi_unregister_transport_device(xport);
> +	rmi_unregister_transport_device(&rmi_i2c->xport);
>
>   	if (pdata->gpio_config)
>   		pdata->gpio_config(pdata->gpio_data, false);


--

Christopher Heiny
Senior Staff Firmware Engineer
Synaptics Incorporated
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