[PATCH v5 3/3] I2C: mediatek: Add driver for MediaTek MT8173 I2C controller
Eddie Huang
eddie.huang at mediatek.com
Mon Mar 30 01:05:19 PDT 2015
Hi Sascha,
On Mon, 2015-03-23 at 08:39 +0100, Sascha Hauer wrote:
> On Sat, Mar 21, 2015 at 02:05:22PM +0800, Eddie Huang wrote:
> > Add mediatek MT8173 I2C controller driver. Compare to I2C controller
> > of earlier mediatek SoC, MT8173 fix write-then-read limitation, and
> > also increase message size to 64kb.
> >
>
> [...]
>
> > +static const struct i2c_adapter_quirks mt8173_i2c_quirks = {
> > + .max_num_msgs = MAX_MSG_NUM_MT8173,
> > + .max_write_len = MAX_DMA_TRANS_SIZE_MT8173,
> > + .max_read_len = MAX_DMA_TRANS_SIZE_MT8173,
> > + .max_comb_1st_msg_len = MAX_DMA_TRANS_SIZE_MT8173,
> > + .max_comb_2nd_msg_len = MAX_WRRD_TRANS_SIZE_MT8173,
> > +};
> > +
> > static int mtk_i2c_probe(struct platform_device *pdev)
> > {
> > int ret = 0;
> > @@ -587,7 +626,8 @@ static int mtk_i2c_probe(struct platform_device *pdev)
> > return -EINVAL;
> >
> > i2c->platform_compat = mtk_get_device_prop(pdev);
> > - if (i2c->have_pmic && (i2c->platform_compat & COMPAT_MT6577))
> > + if (i2c->have_pmic && (i2c->platform_compat &
> > + (COMPAT_MT6577 | COMPAT_MT8173)))
> > return -EINVAL;
> >
> > res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > @@ -613,7 +653,10 @@ static int mtk_i2c_probe(struct platform_device *pdev)
> > i2c->adap.dev.parent = &pdev->dev;
> > i2c->adap.owner = THIS_MODULE;
> > i2c->adap.algo = &mtk_i2c_algorithm;
> > - i2c->adap.quirks = &mt6577_i2c_quirks;
> > + if (i2c->platform_compat & COMPAT_MT8173)
> > + i2c->adap.quirks = &mt8173_i2c_quirks;
> > + else
> > + i2c->adap.quirks = &mt6577_i2c_quirks;
>
> Instead of putting an integer into struct of_device_id you should
> introduce a
>
> struct mtk_i2c_data {
> struct i2c_adapter_quirks quirks;
> int compat;
> /* Additional SoC specific data */
> };
>
> and put a pointer to this directly into the of_device_id. This way you
> need less casting and can put newly discovered differences diretly into
> some data struct and don't have to introduce if(socxy) ... else ...
> everytime.
>
Thanks your suggestion. I will use capability struct like
struct mtk_i2c_compatible {
unsigned char pmic_i2c;
unsigned char dcm;
unsigned char auto_restart;
const struct i2c_adapter_quirks *quirks;
};
And pass in of_device_id, then remove all if(socxy).... else ... in
driver.
Eddie
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