Messages in this thread | | | Date | Mon, 27 Aug 2012 11:49:21 -0700 | Subject | Re: [RFC PATCH 5/17] input: rmidev character driver for RMI4 sensors | From | Linus Walleij <> |
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On Fri, Aug 17, 2012 at 3:17 PM, Christopher Heiny <cheiny@synaptics.com> wrote:
> Driver for Synaptics touchscreens using RMI4 protocol.
Really? This looks more like some custom char driver to get a pipe into the device from userspace. Put in a proper description of what this is for.
If the purpose is to read/write arbitrary addresses in the device, you should use regmap's debugfs interface for this instead, it is much better suited for the task.
(...) > +#define RMI_CHAR_DEV_TMPBUF_SZ 128 > +#define RMI_REG_ADDR_PAGE_SELECT 0xFF > +#define REG_ADDR_LIMIT 0xFFFF > + > +struct rmidev_data { > + /* mutex for file operation*/ > + struct mutex file_mutex; > + /* main char dev structure */ > + struct cdev main_dev; > + > + /* pointer to the corresponding RMI4 device. We use this to do */ > + /* read, write, etc. */ > + struct rmi_device *rmi_dev; > + /* reference count */ > + int ref_count;
Something tells me you should atleast use <linux/kref.h> for this. It also solves a few atomicity problems in a good standard way. See Documentation/kref.txt
> +/*store dynamically allocated major number of char device*/ > +static int rmidev_major_num;
You need to patch your desired major number into Documentation/devices.txt
> +static struct class *rmidev_device_class;
Last time discussed with Greg, class devices were deprecated, and you should just use a bus instead. (But not sure.)
Yours, Linus Walleij
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