Re: [PATCH] ACPI: support for NXP i2c controller

[Oleksij Rempel]

One more question,

On 02.09.19 22:56, Rafael J. Wysocki wrote:
> On Thu, Jul 11, 2019 at 12:35 PM Chuanhua Han <chuanhua.han@xxxxxxx> wrote:
> > Enable NXP i2c controller to boot with ACPI
> >
> > Signed-off-by: Meenakshi Aggarwal <meenakshi.aggarwal@xxxxxxx>
> > Signed-off-by: Udit Kumar <udit.kumar@xxxxxxx>
> > Signed-off-by: Chuanhua Han <chuanhua.han@xxxxxxx>
>
> Wolfram, any objections to this from the i2c side?
>
> > ---
> >   drivers/acpi/acpi_apd.c      |  6 ++++++
> >   drivers/i2c/busses/i2c-imx.c | 15 +++++++++++++++
> >   2 files changed, 21 insertions(+)
> >
> > diff --git a/drivers/acpi/acpi_apd.c b/drivers/acpi/acpi_apd.c
> > index ff47317..cf8566c 100644
> > --- a/drivers/acpi/acpi_apd.c
> > +++ b/drivers/acpi/acpi_apd.c
> > @@ -165,6 +165,11 @@ static const struct apd_device_desc thunderx2_i2c_desc = {
> >          .fixed_clk_rate = 125000000,
> >   };
> >
> > +static const struct apd_device_desc nxp_i2c_desc = {
> > +       .setup = acpi_apd_setup,
> > +       .fixed_clk_rate = 350000000,
> > +};

I'm not ACPI expert, so need here some help for understanding. Here is ACPI table for 
NXP0001 id (found on the internet):
+  Device(I2C0) {
+    Name(_HID, "NXP0001")
+    Name(_UID, 0)
+    Name(_CRS, ResourceTemplate() {
+      Memory32Fixed(ReadWrite, I2C0_BASE, I2C_LEN)
+      Interrupt(ResourceConsumer, Level, ActiveHigh, Shared) { I2C0_IT }
+    }) // end of _CRS for i2c0 device
+    Name (_DSD, Package () {
+      ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
+      Package () {
+         Package () {"clock-frequency", DEFAULT_PLAT_FREQ}, //This is device specific 
data, Need to see how to pass clk stuff
+      }
+    })

Should kernel some how get proper clock-frequency from the ACPI? Or we still need to use 
hard coded .fixed_clk_rate in the kernel?


> >   static const struct apd_device_desc hip08_spi_desc = {
> >          .setup = acpi_apd_setup,
> >          .fixed_clk_rate = 250000000,
> > @@ -238,6 +243,7 @@ static const struct acpi_device_id acpi_apd_device_ids[] = {
> >          { "HISI02A1", APD_ADDR(hip07_i2c_desc) },
> >          { "HISI02A2", APD_ADDR(hip08_i2c_desc) },
> >          { "HISI0173", APD_ADDR(hip08_spi_desc) },
> > +       { "NXP0001", APD_ADDR(nxp_i2c_desc) },
> >   #endif
> >          { }
> >   };
> > diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> > index b1b8b93..99f9b96 100644
> > --- a/drivers/i2c/busses/i2c-imx.c
> > +++ b/drivers/i2c/busses/i2c-imx.c
> > @@ -44,6 +44,7 @@
> >   #include <linux/pm_runtime.h>
> >   #include <linux/sched.h>
> >   #include <linux/slab.h>
> > +#include <linux/acpi.h>
> >
> >   /* This will be the driver name the kernel reports */
> >   #define DRIVER_NAME "imx-i2c"
> > @@ -255,6 +256,12 @@ static const struct of_device_id i2c_imx_dt_ids[] = {
> >   };
> >   MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids);
> >
> > +static const struct acpi_device_id i2c_imx_acpi_ids[] = {
> > +       {"NXP0001", .driver_data = (kernel_ulong_t)&vf610_i2c_hwdata},
> > +       { }
> > +};
> > +MODULE_DEVICE_TABLE(acpi, i2c_imx_acpi_ids);
> > +
> >   static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx)
> >   {
> >          return i2c_imx->hwdata->devtype == IMX1_I2C;
> > @@ -1052,6 +1059,9 @@ static int i2c_imx_probe(struct platform_device *pdev)
> >   {
> >          const struct of_device_id *of_id = of_match_device(i2c_imx_dt_ids,
> >                                                             &pdev->dev);
> > +       const struct acpi_device_id *acpi_id =
> > +                       acpi_match_device(i2c_imx_acpi_ids,
> > +                                         &pdev->dev);
> >          struct imx_i2c_struct *i2c_imx;
> >          struct resource *res;
> >          struct imxi2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
> > @@ -1079,6 +1089,9 @@ static int i2c_imx_probe(struct platform_device *pdev)
> >
> >          if (of_id)
> >                  i2c_imx->hwdata = of_id->data;
> > +       else if (acpi_id)
> > +               i2c_imx->hwdata = (struct imx_i2c_hwdata *)
> > +                               acpi_id->driver_data;
> >          else
> >                  i2c_imx->hwdata = (struct imx_i2c_hwdata *)
> >                                  platform_get_device_id(pdev)->driver_data;
> > @@ -1091,6 +1104,7 @@ static int i2c_imx_probe(struct platform_device *pdev)
> >          i2c_imx->adapter.nr             = pdev->id;
> >          i2c_imx->adapter.dev.of_node    = pdev->dev.of_node;
> >          i2c_imx->base                   = base;
> > +       ACPI_COMPANION_SET(&i2c_imx->adapter.dev, ACPI_COMPANION(&pdev->dev));
> >
> >          /* Get I2C clock */
> >          i2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
> > @@ -1253,6 +1267,7 @@ static struct platform_driver i2c_imx_driver = {
> >                  .name = DRIVER_NAME,
> >                  .pm = &i2c_imx_pm_ops,
> >                  .of_match_table = i2c_imx_dt_ids,
> > +               .acpi_match_table = ACPI_PTR(i2c_imx_acpi_ids),
> >          },
> >          .id_table = imx_i2c_devtype,
> >   };
> > --
> > 2.9.5

Kind regards,
Oleksij Rempel

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