[PATCH v1 1/2] platform/x86: intel_pmc_ipc: Use MFD framework to create dependent devices

[sathyanarayanan . kuppuswamy]

From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>

Currently, we have lot of repetitive code in dependent device resource
allocation and device creation handling code. This logic can be improved if
we use MFD framework for dependent device creation. This patch adds this
support.

Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
 drivers/platform/x86/intel_pmc_ipc.c | 401 +++++++++++++----------------------
 1 file changed, 143 insertions(+), 258 deletions(-)

This patch was originally part of "SCU/PMC/PUNIT IPC driver clean up" series. But I have
split them into two sets because we need more thorough review on generic IPC driver
design patches (second set).

https://www.spinics.net/lists/linux-watchdog/msg12796.html

Changes since previous set version (v8):
 * Addressed comments from Heikki and cleaned up some debug messages. 

diff --git a/drivers/platform/x86/intel_pmc_ipc.c b/drivers/platform/x86/intel_pmc_ipc.c
index e03fa314..fadf721 100644
--- a/drivers/platform/x86/intel_pmc_ipc.c
+++ b/drivers/platform/x86/intel_pmc_ipc.c
@@ -20,6 +20,7 @@
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/device.h>
+#include <linux/mfd/core.h>
 #include <linux/pm.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
@@ -88,6 +89,7 @@
 #define PLAT_RESOURCE_ISP_IFACE_INDEX	5
 #define PLAT_RESOURCE_GTD_DATA_INDEX	6
 #define PLAT_RESOURCE_GTD_IFACE_INDEX	7
+#define PLAT_RESOURCE_MEM_MAX_INDEX	8
 #define PLAT_RESOURCE_ACPI_IO_INDEX	0
 
 /*
@@ -106,8 +108,6 @@
 #define TELEM_SSRAM_SIZE		240
 #define TELEM_PMC_SSRAM_OFFSET		0x1B00
 #define TELEM_PUNIT_SSRAM_OFFSET	0x1A00
-#define TCO_PMC_OFFSET			0x8
-#define TCO_PMC_SIZE			0x4
 
 /* PMC register bit definitions */
 
@@ -124,26 +124,10 @@ static struct intel_pmc_ipc_dev {
 	int cmd;
 	struct completion cmd_complete;
 
-	/* The following PMC BARs share the same ACPI device with the IPC */
-	resource_size_t acpi_io_base;
-	int acpi_io_size;
-	struct platform_device *tco_dev;
-
 	/* gcr */
 	void __iomem *gcr_mem_base;
 	bool has_gcr_regs;
 	spinlock_t gcr_lock;
-
-	/* punit */
-	struct platform_device *punit_dev;
-
-	/* Telemetry */
-	resource_size_t telem_pmc_ssram_base;
-	resource_size_t telem_punit_ssram_base;
-	int telem_pmc_ssram_size;
-	int telem_punit_ssram_size;
-	u8 telem_res_inval;
-	struct platform_device *telemetry_dev;
 } ipcdev;
 
 static char *ipc_err_sources[] = {
@@ -508,7 +492,7 @@ static int ipc_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	ret = devm_request_irq(&pdev->dev, pdev->irq, ioc, 0, "intel_pmc_ipc",
 				pmc);
 	if (ret) {
-		dev_err(&pdev->dev, "Failed to request irq\n");
+		dev_err(&pdev->dev, "Failed to request IRQ\n");
 		return ret;
 	}
 
@@ -593,44 +577,6 @@ static const struct attribute_group intel_ipc_group = {
 	.attrs = intel_ipc_attrs,
 };
 
-static struct resource punit_res_array[] = {
-	/* Punit BIOS */
-	{
-		.flags = IORESOURCE_MEM,
-	},
-	{
-		.flags = IORESOURCE_MEM,
-	},
-	/* Punit ISP */
-	{
-		.flags = IORESOURCE_MEM,
-	},
-	{
-		.flags = IORESOURCE_MEM,
-	},
-	/* Punit GTD */
-	{
-		.flags = IORESOURCE_MEM,
-	},
-	{
-		.flags = IORESOURCE_MEM,
-	},
-};
-
-#define TCO_RESOURCE_ACPI_IO		0
-#define TCO_RESOURCE_SMI_EN_IO		1
-#define TCO_RESOURCE_GCR_MEM		2
-static struct resource tco_res[] = {
-	/* ACPI - TCO */
-	{
-		.flags = IORESOURCE_IO,
-	},
-	/* ACPI - SMI */
-	{
-		.flags = IORESOURCE_IO,
-	},
-};
-
 static struct itco_wdt_platform_data tco_info = {
 	.name = "Apollo Lake SoC",
 	.version = 5,
@@ -638,234 +584,182 @@ static struct itco_wdt_platform_data tco_info = {
 	.update_no_reboot_bit = update_no_reboot_bit,
 };
 
-#define TELEMETRY_RESOURCE_PUNIT_SSRAM	0
-#define TELEMETRY_RESOURCE_PMC_SSRAM	1
-static struct resource telemetry_res[] = {
-	/*Telemetry*/
-	{
-		.flags = IORESOURCE_MEM,
-	},
-	{
-		.flags = IORESOURCE_MEM,
-	},
-};
-
-static int ipc_create_punit_device(void)
+static int ipc_create_punit_device(struct platform_device *pdev)
 {
-	struct platform_device *pdev;
-	const struct platform_device_info pdevinfo = {
-		.parent = ipcdev.dev,
-		.name = PUNIT_DEVICE_NAME,
-		.id = -1,
-		.res = punit_res_array,
-		.num_res = ARRAY_SIZE(punit_res_array),
+	static struct resource punit_res[PLAT_RESOURCE_MEM_MAX_INDEX];
+	static struct mfd_cell punit_cell;
+	struct resource *res;
+	int ret, mindex, pindex = 0;
+
+	for (mindex = 0; mindex <= PLAT_RESOURCE_MEM_MAX_INDEX; mindex++) {
+
+		res = platform_get_resource(pdev, IORESOURCE_MEM, mindex);
+
+		switch (mindex) {
+		/* Get PUNIT resources */
+		case PLAT_RESOURCE_BIOS_DATA_INDEX:
+		case PLAT_RESOURCE_BIOS_IFACE_INDEX:
+			/* BIOS resources are required, so return error if not
+			 * available
+			 */
+			if (!res) {
+				dev_err(&pdev->dev,
+					"Failed to get PUNIT MEM resource %d\n",
+					pindex);
+				return -ENXIO;
+			}
+		case PLAT_RESOURCE_ISP_DATA_INDEX:
+		case PLAT_RESOURCE_ISP_IFACE_INDEX:
+		case PLAT_RESOURCE_GTD_DATA_INDEX:
+		case PLAT_RESOURCE_GTD_IFACE_INDEX:
+			/* if valid resource found, copy the resource to PUNIT
+			 * resource
+			 */
+			if (res)
+				memcpy(&punit_res[pindex], res, sizeof(*res));
+			punit_res[pindex].flags = IORESOURCE_MEM;
+			pindex++;
+			break;
 		};
+	}
 
-	pdev = platform_device_register_full(&pdevinfo);
-	if (IS_ERR(pdev))
-		return PTR_ERR(pdev);
+	/* Create PUNIT IPC MFD cell */
+	punit_cell.name = PUNIT_DEVICE_NAME;
+	punit_cell.num_resources = ARRAY_SIZE(punit_res);
+	punit_cell.resources = punit_res;
+	punit_cell.ignore_resource_conflicts = 1;
 
-	ipcdev.punit_dev = pdev;
+	ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE, &punit_cell,
+				   1, NULL, 0, NULL);
 
-	return 0;
+	dev_dbg(&pdev->dev, "Successfully created PUNIT device\n");
+
+	return ret;
 }
 
-static int ipc_create_tco_device(void)
+static int ipc_create_wdt_device(struct platform_device *pdev)
 {
-	struct platform_device *pdev;
+	static struct resource wdt_ipc_res[2];
+	static struct mfd_cell wdt_cell;
 	struct resource *res;
-	const struct platform_device_info pdevinfo = {
-		.parent = ipcdev.dev,
-		.name = TCO_DEVICE_NAME,
-		.id = -1,
-		.res = tco_res,
-		.num_res = ARRAY_SIZE(tco_res),
-		.data = &tco_info,
-		.size_data = sizeof(tco_info),
-		};
+	int ret;
 
-	res = tco_res + TCO_RESOURCE_ACPI_IO;
-	res->start = ipcdev.acpi_io_base + TCO_BASE_OFFSET;
-	res->end = res->start + TCO_REGS_SIZE - 1;
+	/* If we have ACPI based watchdog use that instead, othewise create
+	 * a MFD cell for iTCO watchdog
+	 */
+	if (acpi_has_watchdog())
+		return 0;
 
-	res = tco_res + TCO_RESOURCE_SMI_EN_IO;
-	res->start = ipcdev.acpi_io_base + SMI_EN_OFFSET;
-	res->end = res->start + SMI_EN_SIZE - 1;
+	/* Get iTCO watchdog resources */
+	res = platform_get_resource(pdev, IORESOURCE_IO,
+				    PLAT_RESOURCE_ACPI_IO_INDEX);
+	if (!res) {
+		dev_err(&pdev->dev, "Failed to get WDT resource\n");
+		return -ENXIO;
+	}
 
-	pdev = platform_device_register_full(&pdevinfo);
-	if (IS_ERR(pdev))
-		return PTR_ERR(pdev);
+	wdt_ipc_res[0].start = res->start + TCO_BASE_OFFSET;
+	wdt_ipc_res[0].end = res->start +
+		TCO_BASE_OFFSET + TCO_REGS_SIZE - 1;
+	wdt_ipc_res[0].flags = IORESOURCE_IO;
+	wdt_ipc_res[1].start = res->start + SMI_EN_OFFSET;
+	wdt_ipc_res[1].end = res->start +
+		SMI_EN_OFFSET + SMI_EN_SIZE - 1;
+	wdt_ipc_res[1].flags = IORESOURCE_IO;
 
-	ipcdev.tco_dev = pdev;
+	wdt_cell.name = TCO_DEVICE_NAME;
+	wdt_cell.platform_data = &tco_info;
+	wdt_cell.pdata_size = sizeof(tco_info);
+	wdt_cell.num_resources = ARRAY_SIZE(wdt_ipc_res);
+	wdt_cell.resources = wdt_ipc_res;
+	wdt_cell.ignore_resource_conflicts = 1;
 
-	return 0;
+	ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE, &wdt_cell,
+				   1, NULL, 0, NULL);
+
+	dev_dbg(&pdev->dev, "Successfully created watchdog device\n");
+
+	return ret;
 }
 
-static int ipc_create_telemetry_device(void)
+static int ipc_create_telemetry_device(struct platform_device *pdev)
 {
-	struct platform_device *pdev;
+	static struct resource telemetry_ipc_res[2];
+	static struct mfd_cell telemetry_cell;
 	struct resource *res;
-	const struct platform_device_info pdevinfo = {
-		.parent = ipcdev.dev,
-		.name = TELEMETRY_DEVICE_NAME,
-		.id = -1,
-		.res = telemetry_res,
-		.num_res = ARRAY_SIZE(telemetry_res),
-		};
+	int ret;
 
-	res = telemetry_res + TELEMETRY_RESOURCE_PUNIT_SSRAM;
-	res->start = ipcdev.telem_punit_ssram_base;
-	res->end = res->start + ipcdev.telem_punit_ssram_size - 1;
+	/* Get telemetry resources */
+	res = platform_get_resource(pdev, IORESOURCE_MEM,
+				    PLAT_RESOURCE_TELEM_SSRAM_INDEX);
+	if (!res) {
+		dev_err(&pdev->dev, "Failed to get telemetry resource\n");
+		return -ENXIO;
+	}
 
-	res = telemetry_res + TELEMETRY_RESOURCE_PMC_SSRAM;
-	res->start = ipcdev.telem_pmc_ssram_base;
-	res->end = res->start + ipcdev.telem_pmc_ssram_size - 1;
+	telemetry_ipc_res[0].start = res->start + TELEM_PUNIT_SSRAM_OFFSET;
+	telemetry_ipc_res[0].end = res->start +
+		TELEM_PUNIT_SSRAM_OFFSET + TELEM_SSRAM_SIZE - 1;
+	telemetry_ipc_res[0].flags = IORESOURCE_MEM;
+	telemetry_ipc_res[1].start = res->start + TELEM_PMC_SSRAM_OFFSET;
+	telemetry_ipc_res[1].end = res->start +
+		TELEM_PMC_SSRAM_OFFSET + TELEM_SSRAM_SIZE - 1;
+	telemetry_ipc_res[1].flags = IORESOURCE_MEM;
 
-	pdev = platform_device_register_full(&pdevinfo);
-	if (IS_ERR(pdev))
-		return PTR_ERR(pdev);
+	telemetry_cell.name = TELEMETRY_DEVICE_NAME;
+	telemetry_cell.num_resources = ARRAY_SIZE(telemetry_ipc_res);
+	telemetry_cell.resources = telemetry_ipc_res;
+	telemetry_cell.ignore_resource_conflicts = 1;
 
-	ipcdev.telemetry_dev = pdev;
+	ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
+				   &telemetry_cell, 1, NULL, 0, NULL);
 
-	return 0;
+	dev_dbg(&pdev->dev, "Successfully created telemetry device\n");
+
+	return ret;
 }
 
-static int ipc_create_pmc_devices(void)
+static int ipc_create_pmc_devices(struct platform_device *pdev)
 {
 	int ret;
 
-	/* If we have ACPI based watchdog use that instead */
-	if (!acpi_has_watchdog()) {
-		ret = ipc_create_tco_device();
-		if (ret) {
-			dev_err(ipcdev.dev, "Failed to add tco platform device\n");
-			return ret;
-		}
-	}
+	ret = ipc_create_punit_device(pdev);
+	if (ret < 0)
+		return ret;
 
-	ret = ipc_create_punit_device();
-	if (ret) {
-		dev_err(ipcdev.dev, "Failed to add punit platform device\n");
-		platform_device_unregister(ipcdev.tco_dev);
-	}
+	ret = ipc_create_wdt_device(pdev);
+	if (ret < 0)
+		return ret;
 
-	if (!ipcdev.telem_res_inval) {
-		ret = ipc_create_telemetry_device();
-		if (ret)
-			dev_warn(ipcdev.dev,
-				"Failed to add telemetry platform device\n");
-	}
+	ret = ipc_create_telemetry_device(pdev);
+	if (ret < 0)
+		return ret;
 
-	return ret;
+	return 0;
 }
 
 static int ipc_plat_get_res(struct platform_device *pdev)
 {
-	struct resource *res, *punit_res;
+	struct resource *res;
 	void __iomem *addr;
-	int size;
-
-	res = platform_get_resource(pdev, IORESOURCE_IO,
-				    PLAT_RESOURCE_ACPI_IO_INDEX);
-	if (!res) {
-		dev_err(&pdev->dev, "Failed to get io resource\n");
-		return -ENXIO;
-	}
-	size = resource_size(res);
-	ipcdev.acpi_io_base = res->start;
-	ipcdev.acpi_io_size = size;
-	dev_info(&pdev->dev, "io res: %pR\n", res);
-
-	punit_res = punit_res_array;
-	/* This is index 0 to cover BIOS data register */
-	res = platform_get_resource(pdev, IORESOURCE_MEM,
-				    PLAT_RESOURCE_BIOS_DATA_INDEX);
-	if (!res) {
-		dev_err(&pdev->dev, "Failed to get res of punit BIOS data\n");
-		return -ENXIO;
-	}
-	*punit_res = *res;
-	dev_info(&pdev->dev, "punit BIOS data res: %pR\n", res);
-
-	/* This is index 1 to cover BIOS interface register */
-	res = platform_get_resource(pdev, IORESOURCE_MEM,
-				    PLAT_RESOURCE_BIOS_IFACE_INDEX);
-	if (!res) {
-		dev_err(&pdev->dev, "Failed to get res of punit BIOS iface\n");
-		return -ENXIO;
-	}
-	*++punit_res = *res;
-	dev_info(&pdev->dev, "punit BIOS interface res: %pR\n", res);
-
-	/* This is index 2 to cover ISP data register, optional */
-	res = platform_get_resource(pdev, IORESOURCE_MEM,
-				    PLAT_RESOURCE_ISP_DATA_INDEX);
-	++punit_res;
-	if (res) {
-		*punit_res = *res;
-		dev_info(&pdev->dev, "punit ISP data res: %pR\n", res);
-	}
-
-	/* This is index 3 to cover ISP interface register, optional */
-	res = platform_get_resource(pdev, IORESOURCE_MEM,
-				    PLAT_RESOURCE_ISP_IFACE_INDEX);
-	++punit_res;
-	if (res) {
-		*punit_res = *res;
-		dev_info(&pdev->dev, "punit ISP interface res: %pR\n", res);
-	}
-
-	/* This is index 4 to cover GTD data register, optional */
-	res = platform_get_resource(pdev, IORESOURCE_MEM,
-				    PLAT_RESOURCE_GTD_DATA_INDEX);
-	++punit_res;
-	if (res) {
-		*punit_res = *res;
-		dev_info(&pdev->dev, "punit GTD data res: %pR\n", res);
-	}
-
-	/* This is index 5 to cover GTD interface register, optional */
-	res = platform_get_resource(pdev, IORESOURCE_MEM,
-				    PLAT_RESOURCE_GTD_IFACE_INDEX);
-	++punit_res;
-	if (res) {
-		*punit_res = *res;
-		dev_info(&pdev->dev, "punit GTD interface res: %pR\n", res);
-	}
 
+	/* Get IPC resources */
 	res = platform_get_resource(pdev, IORESOURCE_MEM,
 				    PLAT_RESOURCE_IPC_INDEX);
 	if (!res) {
-		dev_err(&pdev->dev, "Failed to get ipc resource\n");
+		dev_err(&pdev->dev, "Failed to get IPC resources\n");
 		return -ENXIO;
 	}
-	size = PLAT_RESOURCE_IPC_SIZE + PLAT_RESOURCE_GCR_SIZE;
-	res->end = res->start + size - 1;
+
+	res->end = res->start +
+		   PLAT_RESOURCE_IPC_SIZE + PLAT_RESOURCE_GCR_SIZE - 1;
 
 	addr = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(addr))
 		return PTR_ERR(addr);
 
 	ipcdev.ipc_base = addr;
-
 	ipcdev.gcr_mem_base = addr + PLAT_RESOURCE_GCR_OFFSET;
-	dev_info(&pdev->dev, "ipc res: %pR\n", res);
-
-	ipcdev.telem_res_inval = 0;
-	res = platform_get_resource(pdev, IORESOURCE_MEM,
-				    PLAT_RESOURCE_TELEM_SSRAM_INDEX);
-	if (!res) {
-		dev_err(&pdev->dev, "Failed to get telemetry ssram resource\n");
-		ipcdev.telem_res_inval = 1;
-	} else {
-		ipcdev.telem_punit_ssram_base = res->start +
-						TELEM_PUNIT_SSRAM_OFFSET;
-		ipcdev.telem_punit_ssram_size = TELEM_SSRAM_SIZE;
-		ipcdev.telem_pmc_ssram_base = res->start +
-						TELEM_PMC_SSRAM_OFFSET;
-		ipcdev.telem_pmc_ssram_size = TELEM_SSRAM_SIZE;
-		dev_info(&pdev->dev, "telemetry ssram res: %pR\n", res);
-	}
 
 	return 0;
 }
@@ -911,7 +805,7 @@ static int ipc_plat_probe(struct platform_device *pdev)
 
 	ipcdev.irq = platform_get_irq(pdev, 0);
 	if (ipcdev.irq < 0) {
-		dev_err(&pdev->dev, "Failed to get irq\n");
+		dev_err(&pdev->dev, "Failed to get IRQ\n");
 		return -EINVAL;
 	}
 
@@ -921,47 +815,38 @@ static int ipc_plat_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	ret = ipc_create_pmc_devices();
+	ret = ipc_create_pmc_devices(pdev);
 	if (ret) {
-		dev_err(&pdev->dev, "Failed to create pmc devices\n");
+		dev_err(&pdev->dev, "Failed to create PMC devices\n");
 		return ret;
 	}
 
-	if (devm_request_irq(&pdev->dev, ipcdev.irq, ioc, IRQF_NO_SUSPEND,
-			     "intel_pmc_ipc", &ipcdev)) {
-		dev_err(&pdev->dev, "Failed to request irq\n");
-		ret = -EBUSY;
-		goto err_irq;
+	ret = devm_request_irq(&pdev->dev, ipcdev.irq, ioc, IRQF_NO_SUSPEND,
+			       "intel_pmc_ipc", &ipcdev);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to request IRQ\n");
+		return ret;
 	}
 
 	ret = sysfs_create_group(&pdev->dev.kobj, &intel_ipc_group);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to create sysfs group %d\n",
 			ret);
-		goto err_sys;
+		devm_free_irq(&pdev->dev, ipcdev.irq, &ipcdev);
+		return ret;
 	}
 
 	ipcdev.has_gcr_regs = true;
 
 	return 0;
-err_sys:
-	devm_free_irq(&pdev->dev, ipcdev.irq, &ipcdev);
-err_irq:
-	platform_device_unregister(ipcdev.tco_dev);
-	platform_device_unregister(ipcdev.punit_dev);
-	platform_device_unregister(ipcdev.telemetry_dev);
-
-	return ret;
 }
 
 static int ipc_plat_remove(struct platform_device *pdev)
 {
 	sysfs_remove_group(&pdev->dev.kobj, &intel_ipc_group);
 	devm_free_irq(&pdev->dev, ipcdev.irq, &ipcdev);
-	platform_device_unregister(ipcdev.tco_dev);
-	platform_device_unregister(ipcdev.punit_dev);
-	platform_device_unregister(ipcdev.telemetry_dev);
 	ipcdev.dev = NULL;
+
 	return 0;
 }
 
@@ -980,12 +865,12 @@ static int __init intel_pmc_ipc_init(void)
 
 	ret = platform_driver_register(&ipc_plat_driver);
 	if (ret) {
-		pr_err("Failed to register PMC ipc platform driver\n");
+		pr_err("Failed to register PMC IPC platform driver\n");
 		return ret;
 	}
 	ret = pci_register_driver(&ipc_pci_driver);
 	if (ret) {
-		pr_err("Failed to register PMC ipc pci driver\n");
+		pr_err("Failed to register PMC IPC PCI driver\n");
 		platform_driver_unregister(&ipc_plat_driver);
 		return ret;
 	}
-- 
2.7.4