[PATCH v7 02/17] i2c: designware: Add Apollo Lake support

[Bin Meng]

On Mon, Dec 9, 2019 at 8:32 AM Simon Glass <sjg at chromium.org> wrote:
>
> For Apollo Lake we need to take the I2C bus controller out of reset before
> using this. Add this functionality to the driver.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> Reviewed-by: Heiko Schocher <hs at denx.de>
> ---
>
> Changes in v7: None
> Changes in v6:
> - Add .driver_data in the designware_pci_supported array
> - Add a comment about VANILLA
> - Move lpss_reset_release() to this commit
>
> Changes in v5:
> - Drop unrelated change metioned by Heiko
>
> Changes in v4:
> - apollolake -> Apollo Lake
>
> Changes in v3:
> - Add a weak function to avoid errors on other platforms
>
> Changes in v2: None
>
>  drivers/i2c/designware_i2c_pci.c | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
>
> diff --git a/drivers/i2c/designware_i2c_pci.c b/drivers/i2c/designware_i2c_pci.c
> index bb1f809af3..a3586371dc 100644
> --- a/drivers/i2c/designware_i2c_pci.c
> +++ b/drivers/i2c/designware_i2c_pci.c
> @@ -8,8 +8,14 @@
>  #include <common.h>
>  #include <dm.h>
>  #include <spl.h>
> +#include <asm/lpss.h>
>  #include "designware_i2c.h"
>
> +enum {
> +       VANILLA         = 0,    /* standard I2C with no tweaks */
> +       INTEL_APL,              /* Apollo Lake I2C */
> +};
> +
>  /* BayTrail HCNT/LCNT/SDA hold time */
>  static struct dw_scl_sda_cfg byt_config = {
>         .ss_hcnt = 0x200,
> @@ -19,6 +25,9 @@ static struct dw_scl_sda_cfg byt_config = {
>         .sda_hold = 0x6,
>  };
>
> +/* Have a weak function for now - possibly should be a new uclass */
> +__weak void lpss_reset_release(void *regs);
> +
>  static int designware_i2c_pci_ofdata_to_platdata(struct udevice *dev)
>  {
>         struct dw_i2c *priv = dev_get_priv(dev);
> @@ -59,6 +68,15 @@ static int designware_i2c_pci_ofdata_to_platdata(struct udevice *dev)
>
>  static int designware_i2c_pci_probe(struct udevice *dev)
>  {
> +       struct dw_i2c *priv = dev_get_priv(dev);
> +
> +       if (dev_get_driver_data(dev) == INTEL_APL) {
> +               /* Ensure controller is in D0 state */
> +               lpss_set_power_state(dev, STATE_D0);
> +
> +               lpss_reset_release(priv->regs);
> +       }
> +
>         return designware_i2c_probe(dev);
>  }
>
> @@ -88,6 +106,7 @@ static int designware_i2c_pci_bind(struct udevice *dev)
>
>  static const struct udevice_id designware_i2c_pci_ids[] = {
>         { .compatible = "snps,designware-i2c-pci" },
> +       { .compatible = "intel,apl-i2c", INTEL_APL },

nits: .data = INTEL_APL to make it clear

>         { }
>  };
>
> @@ -113,6 +132,12 @@ static struct pci_device_id designware_pci_supported[] = {
>         { PCI_VDEVICE(INTEL, 0x0f45) },
>         { PCI_VDEVICE(INTEL, 0x0f46) },
>         { PCI_VDEVICE(INTEL, 0x0f47) },
> +       { PCI_VDEVICE(INTEL, 0x5aac), .driver_data = INTEL_APL },
> +       { PCI_VDEVICE(INTEL, 0x5aae), .driver_data = INTEL_APL },
> +       { PCI_VDEVICE(INTEL, 0x5ab0), .driver_data = INTEL_APL },
> +       { PCI_VDEVICE(INTEL, 0x5ab2), .driver_data = INTEL_APL },
> +       { PCI_VDEVICE(INTEL, 0x5ab4), .driver_data = INTEL_APL },
> +       { PCI_VDEVICE(INTEL, 0x5ab6), .driver_data = INTEL_APL },
>         {},
>  };
>

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>