[PATCH v6 7/8] soc/tegra: fuse: Add ACPI support for Tegra194 and Tegra234

[Kartik]

Add ACPI support for Tegra194 & Tegra243 SoC's. This requires
following modifications to the probe when ACPI boot is used:
 - Initialize soc data.
 - Add nvmem lookups.
 - Register soc device.
 - use devm_clk_get_optional() instead of devm_clk_get() to get
   fuse->clk, as fuse clocks are not required when using ACPI boot.

Also, drop '__init' keyword for tegra_soc_device_register() as this is also
used by tegra_fuse_probe() and use dev_err_probe() wherever applicable.

Signed-off-by: Kartik <kkartik@xxxxxxxxxx>
---
v4 -> v5:
	* Fix build warnings seen with tegra_fuse_acpi_match when
	  CONFIG_ACPI is disabled.
v3 -> v4:
	* Use dev_fwnode() to dereference the fwnode.
	* Add MODULE_DEVICE_TABLE for tegra_fuse_acpi_match.
	* Moved tegra_fuse_acpi_match above tegra_fuse_driver i.e.,
	  close to the user of tegra_fuse_acpi_match.
	* Moved the improvements made to fuse clk/rst get error handling
	  to separate patch.
	* Moved ACPI related initialization after fuse->base is
	  initialized in tegra_fuse_probe(), as this triggers a warning
	  in tegra_fuse_read_early() which is called from
	  fuse->soc->init().
v2 -> v3:
	* Updated commit message to specify changes related to inclusion
	  of dev_err_probe().

v1 -> v2:
	* Updated ACPI ID table 'tegra_fuse_acpi_match'.
	* Removed ',' after "{ /* sentinel */ }" in
	  'tegra_fuse_acpi_match'.
	* Using same probe for ACPI and device-tree boot.
	* Added code for required initialization when ACPI boot is used.
	* Make clocks optional for ACPI.
	* Use dev_err_probe() wherever applicable.
	* Check if clock has been initialized only when device-tree
	  boot is used.
---
 drivers/soc/tegra/fuse/fuse-tegra.c | 52 +++++++++++++++++++++++++++--
 1 file changed, 49 insertions(+), 3 deletions(-)

diff --git a/drivers/soc/tegra/fuse/fuse-tegra.c b/drivers/soc/tegra/fuse/fuse-tegra.c
index 7a93c6512f7b..39a59545c93f 100644
--- a/drivers/soc/tegra/fuse/fuse-tegra.c
+++ b/drivers/soc/tegra/fuse/fuse-tegra.c
@@ -3,11 +3,13 @@
  * Copyright (c) 2013-2023, NVIDIA CORPORATION.  All rights reserved.
  */
 
+#include <linux/acpi.h>
 #include <linux/clk.h>
 #include <linux/device.h>
 #include <linux/kobject.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/mod_devicetable.h>
 #include <linux/nvmem-consumer.h>
 #include <linux/nvmem-provider.h>
 #include <linux/of.h>
@@ -152,7 +154,38 @@ static int tegra_fuse_probe(struct platform_device *pdev)
 		return PTR_ERR(fuse->base);
 	fuse->phys = res->start;
 
-	fuse->clk = devm_clk_get(&pdev->dev, "fuse");
+	/* Initialize the soc data and lookups if using ACPI boot. */
+	if (is_acpi_node(dev_fwnode(&pdev->dev)) && !fuse->soc) {
+		u8 chip;
+
+		tegra_acpi_init_apbmisc();
+
+		chip = tegra_get_chip_id();
+		switch (chip) {
+#if defined(CONFIG_ARCH_TEGRA_194_SOC)
+		case TEGRA194:
+			fuse->soc = &tegra194_fuse_soc;
+			break;
+#endif
+#if defined(CONFIG_ARCH_TEGRA_234_SOC)
+		case TEGRA234:
+			fuse->soc = &tegra234_fuse_soc;
+			break;
+#endif
+		default:
+			return dev_err_probe(&pdev->dev, -EINVAL, "Unsupported SoC: %02x\n", chip);
+		}
+
+		fuse->soc->init(fuse);
+		tegra_fuse_print_sku_info(&tegra_sku_info);
+		tegra_soc_device_register();
+
+		err = tegra_fuse_add_lookups(fuse);
+		if (err)
+			return dev_err_probe(&pdev->dev, err, "failed to add FUSE lookups\n");
+	}
+
+	fuse->clk = devm_clk_get_optional(&pdev->dev, "fuse");
 	if (IS_ERR(fuse->clk))
 		return dev_err_probe(&pdev->dev, PTR_ERR(fuse->clk), "failed to get FUSE clock\n");
 
@@ -275,10 +308,17 @@ static const struct dev_pm_ops tegra_fuse_pm = {
 	SET_SYSTEM_SLEEP_PM_OPS(tegra_fuse_suspend, tegra_fuse_resume)
 };
 
+static const struct acpi_device_id __maybe_unused tegra_fuse_acpi_match[] = {
+	{ "NVDA200F" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(acpi, tegra_fuse_acpi_match);
+
 static struct platform_driver tegra_fuse_driver = {
 	.driver = {
 		.name = "tegra-fuse",
 		.of_match_table = tegra_fuse_match,
+		.acpi_match_table = ACPI_PTR(tegra_fuse_acpi_match),
 		.pm = &tegra_fuse_pm,
 		.suppress_bind_attrs = true,
 	},
@@ -300,7 +340,13 @@ u32 __init tegra_fuse_read_early(unsigned int offset)
 
 int tegra_fuse_readl(unsigned long offset, u32 *value)
 {
-	if (!fuse->read || !fuse->clk)
+	/*
+	 * Wait for fuse->clk to be initialized if device-tree boot is used.
+	 */
+	if (is_of_node(dev_fwnode(fuse->dev)) && !fuse->clk)
+		return -EPROBE_DEFER;
+
+	if (!fuse->read)
 		return -EPROBE_DEFER;
 
 	if (IS_ERR(fuse->clk))
@@ -383,7 +429,7 @@ const struct attribute_group tegra194_soc_attr_group = {
 };
 #endif
 
-struct device * __init tegra_soc_device_register(void)
+struct device *tegra_soc_device_register(void)
 {
 	struct soc_device_attribute *attr;
 	struct soc_device *dev;
-- 
2.34.1