[PATCH v2] i2c: tegra: Add ACPI support - dri-devel - freedesktop.org experimental mailing list

23 Nov 2021

Add support for ACPI based device registration so that the driver
can be also enabled through ACPI table.
Signed-off-by: Akhil R akhilrajeev@nvidia.com
---
 drivers/i2c/busses/i2c-tegra.c | 52 ++++++++++++++++++++++++++++++++----------
 1 file changed, 40 insertions(+), 12 deletions(-)

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index c883044..8e47889 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -6,6 +6,7 @@
  * Author: Colin Cross ccross@android.com
  */
+#include <linux/acpi.h>
 #include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
@@ -608,6 +609,7 @@ static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev)
 static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
 {
    u32 val, clk_divisor, clk_multiplier, tsu_thd, tlow, thigh, non_hs_mode;
+	acpi_handle handle = ACPI_HANDLE(i2c_dev->dev);
    int err;
/*
@@ -618,7 +620,11 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
     * emit a noisy warning on error, which won't stay unnoticed and
     * won't hose machine entirely.
     */
-	err = reset_control_reset(i2c_dev->rst);
+	if (handle && acpi_has_method(handle, "_RST"))
+		err = (acpi_evaluate_object(handle, "_RST", NULL, NULL));
+	else
+		err = reset_control_reset(i2c_dev->rst);
+
    WARN_ON_ONCE(err);
if (i2c_dev->is_dvc)
@@ -1627,12 +1633,12 @@ static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev)
    bool multi_mode;
    int err;
-	err = of_property_read_u32(np, "clock-frequency",
-				   &i2c_dev->bus_clk_rate);
+	err = device_property_read_u32(i2c_dev->dev, "clock-frequency",
+				       &i2c_dev->bus_clk_rate);
    if (err)
    	i2c_dev->bus_clk_rate = I2C_MAX_STANDARD_MODE_FREQ;
-	multi_mode = of_property_read_bool(np, "multi-master");
+	multi_mode = device_property_read_bool(i2c_dev->dev, "multi-master");
    i2c_dev->multimaster_mode = multi_mode;
if (of_device_is_compatible(np, "nvidia,tegra20-i2c-dvc"))
@@ -1642,10 +1648,25 @@ static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev)
    	i2c_dev->is_vi = true;
 }
+static int tegra_i2c_init_reset(struct tegra_i2c_dev *i2c_dev)
+{
+	if (has_acpi_companion(i2c_dev->dev))
+		return 0;
+
+	i2c_dev->rst = devm_reset_control_get_exclusive(i2c_dev->dev, "i2c");
+	if (IS_ERR(i2c_dev->rst))
+		return PTR_ERR(i2c_dev->rst);
+
+	return 0;
+}
+
 static int tegra_i2c_init_clocks(struct tegra_i2c_dev *i2c_dev)
 {
    int err;
+	if (has_acpi_companion(i2c_dev->dev))
+		return 0;
+
    i2c_dev->clocks[i2c_dev->nclocks++].id = "div-clk";
if (i2c_dev->hw == &tegra20_i2c_hw || i2c_dev->hw == &tegra30_i2c_hw)
@@ -1720,7 +1741,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
    init_completion(&i2c_dev->msg_complete);
    init_completion(&i2c_dev->dma_complete);
-	i2c_dev->hw = of_device_get_match_data(&pdev->dev);
+	i2c_dev->hw = device_get_match_data(&pdev->dev);
    i2c_dev->cont_id = pdev->id;
    i2c_dev->dev = &pdev->dev;
@@ -1746,15 +1767,13 @@ static int tegra_i2c_probe(struct platform_device *pdev)
    if (err)
    	return err;
-	i2c_dev->rst = devm_reset_control_get_exclusive(i2c_dev->dev, "i2c");
-	if (IS_ERR(i2c_dev->rst)) {
-		dev_err_probe(i2c_dev->dev, PTR_ERR(i2c_dev->rst),
-			      "failed to get reset control\n");
-		return PTR_ERR(i2c_dev->rst);
-	}
-
    tegra_i2c_parse_dt(i2c_dev);
+	err = tegra_i2c_init_reset(i2c_dev);
+	if (err)
+		return dev_err_probe(i2c_dev->dev, err,
+				      "failed to get reset control\n");
+
    err = tegra_i2c_init_clocks(i2c_dev);
    if (err)
    	return err;
@@ -1923,12 +1942,21 @@ static const struct dev_pm_ops tegra_i2c_pm = {
    		   NULL)
 };
+static const struct acpi_device_id tegra_i2c_acpi_match[] = {
+	{.id = "NVDA0101", .driver_data = (kernel_ulong_t)&tegra210_i2c_hw},
+	{.id = "NVDA0201", .driver_data = (kernel_ulong_t)&tegra186_i2c_hw},
+	{.id = "NVDA0301", .driver_data = (kernel_ulong_t)&tegra194_i2c_hw},
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, tegra_i2c_acpi_match);
+
 static struct platform_driver tegra_i2c_driver = {
    .probe = tegra_i2c_probe,
    .remove = tegra_i2c_remove,
    .driver = {
    	.name = "tegra-i2c",
    	.of_match_table = tegra_i2c_of_match,
+		.acpi_match_table = tegra_i2c_acpi_match,
    	.pm = &tegra_i2c_pm,
    },
 };
-- 
2.7.4


    