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

Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> · Tue, 3 Sep 2019 12:50:03 +0200

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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