Hi Florian,
On Tue, Dec 01, 2015 at 03:03:59PM +0100, Florian Vallee wrote:
> This is based on the I2C implementation of the corresponding linux
> driver. The SPI part was left out.
>
> Tested with an MCP23017.
>
...
> +
> +static int mcp230xx_probe(struct device_d *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + unsigned long driver_data;
> + struct mcp23s08_platform_data *pdata;
> + struct mcp23s08 *mcp;
> + int status;
> +
> + driver_data = 0;
> + pdata = dev->platform_data;
> + if (pdata) {
> + pdata->base = -1;
> + } else {
> + int err;
> +
> + err = dev_get_drvdata(dev, (const void **) &driver_data);
> + if (err)
> + return err;
> +
> + pdata = xzalloc(sizeof(struct mcp23s08_platform_data));
> + pdata->base = -1;
> + }
platform_data should be treated as const by drivers. Please fill in
mcp->chip.base directly instead. Also pdata->base is always initialized
to -1, even when a base is specified it is overwritten. This doesn't
seem to be intended.
> +
> + mcp = xzalloc(sizeof(*mcp));
> + if (!mcp)
> + return -ENOMEM;
xzalloc does not fail. You don't need to check the result.
> +
> + status = mcp23s08_probe_one(mcp, &client->dev, client, client->addr,
> + driver_data, pdata, 0);
> +
> + return status;
> +}
> +
> +static struct platform_device_id mcp230xx_id[] = {
> + { "mcp23008", MCP_TYPE_008 },
> + { "mcp23017", MCP_TYPE_017 },
> + { },
> +};
> +
> +static struct driver_d mcp230xx_driver = {
> + .name = "mcp230xx",
> + .probe = mcp230xx_probe,
> + .id_table = mcp230xx_id,
> +};
> +
> +static int __init mcp23s08_i2c_init(void)
> +{
> + return i2c_driver_register(&mcp230xx_driver);
> +}
> +
> +device_initcall(mcp23s08_i2c_init);
> diff --git a/include/platform_data/mcp23s08.h b/include/platform_data/mcp23s08.h
> new file mode 100644
> index 0000000..aa07d7b
> --- /dev/null
> +++ b/include/platform_data/mcp23s08.h
> @@ -0,0 +1,43 @@
> +
> +/* FIXME driver should be able to handle IRQs... */
> +
> +struct mcp23s08_chip_info {
> + bool is_present; /* true if populated */
> + unsigned pullups; /* BIT(x) means enable pullup x */
> +};
> +
> +struct mcp23s08_platform_data {
> + /* For mcp23s08, up to 4 slaves (numbered 0..3) can share one SPI
> + * chipselect, each providing 1 gpio_chip instance with 8 gpios.
> + * For mpc23s17, up to 8 slaves (numbered 0..7) can share one SPI
> + * chipselect, each providing 1 gpio_chip (port A + port B) with
> + * 16 gpios.
> + */
> + struct mcp23s08_chip_info chip[8];
> +
> + /* "base" is the number of the first GPIO. Dynamic assignment is
> + * not currently supported, and even if there are gaps in chip
> + * addressing the GPIO numbers are sequential .. so for example
> + * if only slaves 0 and 3 are present, their GPIOs range from
> + * base to base+15 (or base+31 for s17 variant).
> + */
> + unsigned base;
> + /* Marks the device as a interrupt controller.
> + * NOTE: The interrupt functionality is only supported for i2c
> + * versions of the chips. The spi chips can also do the interrupts,
> + * but this is not supported by the linux driver yet.
> + */
> + bool irq_controller;
> +
> + /* Sets the mirror flag in the IOCON register. Devices
> + * with two interrupt outputs (these are the devices ending with 17 and
> + * those that have 16 IOs) have two IO banks: IO 0-7 form bank 1 and
> + * IO 8-15 are bank 2. These chips have two different interrupt outputs:
> + * One for bank 1 and another for bank 2. If irq-mirror is set, both
> + * interrupts are generated regardless of the bank that an input change
> + * occurred on. If it is not set, the interrupt are only generated for
> + * the bank they belong to.
> + * On devices with only one interrupt output this property is useless.
> + */
> + bool mirror;
> +};
Everything except 'base' is ignored (well, base is ignored aswell, but
this was probably not intended). Please remove the unused fields.
Sascha
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
_______________________________________________
barebox mailing list
barebox@xxxxxxxxxxxxxxxxxxx
http://lists.infradead.org/mailman/listinfo/barebox
