Re: [PATCH 2/2] i2c: designware-baytrail: Add support for cherrytrail

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Fri, 2016-12-09 at 12:01 +0100, Hans de Goede wrote:
> The cherrytrail punit has the pmic i2c bus access semaphore at a
> different register address.

Thanks for the patch. My comments below.

> --- a/drivers/i2c/busses/i2c-designware-baytrail.c
> +++ b/drivers/i2c/busses/i2c-designware-baytrail.c
> @@ -22,7 +22,8 @@
>  #include "i2c-designware-core.h"
>  
>  #define SEMAPHORE_TIMEOUT	100
> -#define PUNIT_SEMAPHORE		0x7
> +#define PUNIT_SEMAPHORE		((dev->accessor_flags &
> ACCESS_IS_CHERRYTRAIL) \
> +				 ? 0x10e : 0x7)

Personally I don't like this.

What if we do it in a helper function

static u32 get_sem_addr()
{
 ...
 return addr;
}

And user

{
u32 addr = get_sem_addr(...);

iosf...(..., addr, ...);
}


> --- a/drivers/i2c/busses/i2c-designware-core.h
> +++ b/drivers/i2c/busses/i2c-designware-core.h
> @@ -123,6 +123,8 @@ struct dw_i2c_dev {
>  #define ACCESS_SWAP		0x00000001
>  #define ACCESS_16BIT		0x00000002
>  #define ACCESS_INTR_MASK	0x00000004
> +/* Not really an accessor_flag but also set through driver_data */
> +#define ACCESS_IS_CHERRYTRAIL	0x00000008

Don't like it either. Here two ways I see:
Introduce another member to keep non-accessor flags, or rename existing
one and create new flags with some other prefix.

>  
>  extern int i2c_dw_init(struct dw_i2c_dev *dev);
>  extern void i2c_dw_disable(struct dw_i2c_dev *dev);
> diff --git a/drivers/i2c/busses/i2c-designware-pcidrv.c
> b/drivers/i2c/busses/i2c-designware-pcidrv.c
> index 96f8230..d774bab 100644
> --- a/drivers/i2c/busses/i2c-designware-pcidrv.c
> +++ b/drivers/i2c/busses/i2c-designware-pcidrv.c
> @@ -45,6 +45,7 @@ enum dw_pci_ctl_id_t {
>  	medfield,
>  	merrifield,
>  	baytrail,
> +	cherrytrail,
>  	haswell,
>  };
>  
> @@ -174,6 +175,14 @@ static struct dw_pci_controller
> dw_pci_controllers[] = {
>  		.functionality = I2C_FUNC_10BIT_ADDR,
>  		.scl_sda_cfg = &hsw_config,
>  	},

> +	[cherrytrail] = {
> +		.bus_num = -1,
> +		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
> +		.tx_fifo_depth = 32,
> +		.rx_fifo_depth = 32,
> +		.functionality = I2C_FUNC_10BIT_ADDR,
> +		.scl_sda_cfg = &byt_config,

Would be ugly if we actually put... 

> +	},
>  };
>  
>  #ifdef CONFIG_PM
> @@ -241,6 +250,8 @@ static int i2c_dw_pci_probe(struct pci_dev *pdev,
>  	dev->base = pcim_iomap_table(pdev)[0];
>  	dev->dev = &pdev->dev;
>  	dev->irq = pdev->irq;
> +	if (id->driver_data == cherrytrail)
> +		dev->accessor_flags |= ACCESS_IS_CHERRYTRAIL;

...above inside the struct dw_pci_controller?

>  
>  	if (controller->setup) {
>  		r = controller->setup(pdev, controller);
> @@ -321,13 +332,13 @@ static const struct pci_device_id
> i2_designware_pci_ids[] = {
>  	{ PCI_VDEVICE(INTEL, 0x9c61), haswell },
>  	{ PCI_VDEVICE(INTEL, 0x9c62), haswell },
>  	/* Braswell / Cherrytrail */
> -	{ PCI_VDEVICE(INTEL, 0x22C1), baytrail },
> -	{ PCI_VDEVICE(INTEL, 0x22C2), baytrail },
> -	{ PCI_VDEVICE(INTEL, 0x22C3), baytrail },
> -	{ PCI_VDEVICE(INTEL, 0x22C4), baytrail },
> -	{ PCI_VDEVICE(INTEL, 0x22C5), baytrail },
> -	{ PCI_VDEVICE(INTEL, 0x22C6), baytrail },
> -	{ PCI_VDEVICE(INTEL, 0x22C7), baytrail },
> +	{ PCI_VDEVICE(INTEL, 0x22C1), cherrytrail },
> +	{ PCI_VDEVICE(INTEL, 0x22C2), cherrytrail },
> +	{ PCI_VDEVICE(INTEL, 0x22C3), cherrytrail },
> +	{ PCI_VDEVICE(INTEL, 0x22C4), cherrytrail },
> +	{ PCI_VDEVICE(INTEL, 0x22C5), cherrytrail },
> +	{ PCI_VDEVICE(INTEL, 0x22C6), cherrytrail },
> +	{ PCI_VDEVICE(INTEL, 0x22C7), cherrytrail },
>  	{ 0,}
>  };
>  MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids);
> diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c
> b/drivers/i2c/busses/i2c-designware-platdrv.c
> index 0b42a12..8974467 100644
> --- a/drivers/i2c/busses/i2c-designware-platdrv.c
> +++ b/drivers/i2c/busses/i2c-designware-platdrv.c
> @@ -123,7 +123,7 @@ static const struct acpi_device_id
> dw_i2c_acpi_match[] = {
>  	{ "INT3432", 0 },
>  	{ "INT3433", 0 },
>  	{ "80860F41", 0 },
> -	{ "808622C1", 0 },
> +	{ "808622C1", ACCESS_IS_CHERRYTRAIL },
>  	{ "AMD0010", ACCESS_INTR_MASK },
>  	{ "AMDI0010", ACCESS_INTR_MASK },
>  	{ "AMDI0510", 0 },

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy