From: Akhil R <akhilrajeev@nvidia.com>
Date: Thu, 25 Nov 2021 22:23:44 +0530
Subject: i2c: tegra: Add the ACPI support
Git-commit: bd2fdedbf2bac27f4a2ac16b84ab9b9e5f67006c
Patch-mainline: v5.17-rc1
References: jsc#SLE-24569

Add support for the ACPI based device registration so that the driver
can be also enabled through ACPI table.

This does not include the ACPI support for Tegra VI and DVC I2C.

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Acked-by: Ivan T. Ivanov <iivanov@suse.de>
---
 drivers/i2c/busses/i2c-tegra.c |   52 +++++++++++++++++++++++++++++++----------
 1 file changed, 40 insertions(+), 12 deletions(-)

--- 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_loa
 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_i
 	 * 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)
+		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 te
 	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 +1648,26 @@ static void tegra_i2c_parse_dt(struct te
 		i2c_dev->is_vi = true;
 }
 
+static int tegra_i2c_init_reset(struct tegra_i2c_dev *i2c_dev)
+{
+	if (ACPI_HANDLE(i2c_dev->dev))
+		return 0;
+
+	i2c_dev->rst = devm_reset_control_get_exclusive(i2c_dev->dev, "i2c");
+	if (IS_ERR(i2c_dev->rst))
+		return dev_err_probe(i2c_dev->dev, PTR_ERR(i2c_dev->rst),
+				      "failed to get reset control\n");
+
+	return 0;
+}
+
 static int tegra_i2c_init_clocks(struct tegra_i2c_dev *i2c_dev)
 {
 	int err;
 
+	if (ACPI_HANDLE(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 +1742,7 @@ static int tegra_i2c_probe(struct platfo
 	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 +1768,12 @@ static int tegra_i2c_probe(struct platfo
 	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 err;
+
 	err = tegra_i2c_init_clocks(i2c_dev);
 	if (err)
 		return err;
@@ -1923,12 +1942,21 @@ static const struct dev_pm_ops tegra_i2c
 			   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,
 	},
 };