spi: intel: Improve resource mapping

Let's use the pci/platform-specialized functions for mapping a resource,
and pass the mapped address to intel_spi_probe. Benefits are:

- No separate call needed for getting the resource, and no access to
  struct pci_dev internals (pdev->resource[]).

- More user-friendly output in /proc/iomem. In my case:

  before
  80704000-80704fff : 0000:00:1f.5
    80704000-80704fff : 0000:00:1f.5 0000:00:1f.5

  after
  80704000-80704fff : 0000:00:1f.5
    80704000-80704fff : spi_intel_pci

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://patch.msgid.link/2585fa05-60c4-48c4-a838-e87014665ae2@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: hkallweit

drivers/spi/spi-intel-pci.c

@@ -44,6 +44,7 @@ static int intel_spi_pci_probe(struct pci_dev *pdev,
 			       const struct pci_device_id *id)
 {
 	struct intel_spi_boardinfo *info;
+	void __iomem *base;
 	int ret;
 
 	ret = pcim_enable_device(pdev);
@@ -56,7 +57,12 @@ static int intel_spi_pci_probe(struct pci_dev *pdev,
 		return -ENOMEM;
 
 	info->data = pdev;
-	return intel_spi_probe(&pdev->dev, &pdev->resource[0], info);
+
+	base = pcim_iomap_region(pdev, 0, KBUILD_MODNAME);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	return intel_spi_probe(&pdev->dev, base, info);
 }
 
 static const struct pci_device_id intel_spi_pci_ids[] = {

drivers/spi/spi-intel-platform.c

@@ -14,14 +14,17 @@
 static int intel_spi_platform_probe(struct platform_device *pdev)
 {
 	struct intel_spi_boardinfo *info;
-	struct resource *mem;
+	void __iomem *base;
 
 	info = dev_get_platdata(&pdev->dev);
 	if (!info)
 		return -EINVAL;
 
-	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	return intel_spi_probe(&pdev->dev, mem, info);
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	return intel_spi_probe(&pdev->dev, base, info);
 }
 
 static struct platform_driver intel_spi_platform_driver = {

drivers/spi/spi-intel.c

@@ -1467,13 +1467,13 @@ EXPORT_SYMBOL_GPL(intel_spi_groups);
 /**
  * intel_spi_probe() - Probe the Intel SPI flash controller
  * @dev: Pointer to the parent device
- * @mem: MMIO resource
+ * @base: iomapped MMIO resource
  * @info: Platform specific information
  *
  * Probes Intel SPI flash controller and creates the flash chip device.
  * Returns %0 on success and negative errno in case of failure.
  */
-int intel_spi_probe(struct device *dev, struct resource *mem,
+int intel_spi_probe(struct device *dev, void __iomem *base,
 		    const struct intel_spi_boardinfo *info)
 {
 	struct spi_controller *host;
@@ -1488,10 +1488,7 @@ int intel_spi_probe(struct device *dev, struct resource *mem,
 
 	ispi = spi_controller_get_devdata(host);
 
-	ispi->base = devm_ioremap_resource(dev, mem);
-	if (IS_ERR(ispi->base))
-		return PTR_ERR(ispi->base);
-
+	ispi->base = base;
 	ispi->dev = dev;
 	ispi->host = host;
 	ispi->info = info;

drivers/spi/spi-intel.h

@@ -11,11 +11,9 @@
 
 #include <linux/platform_data/x86/spi-intel.h>
 
-struct resource;
-
 extern const struct attribute_group *intel_spi_groups[];
 
-int intel_spi_probe(struct device *dev, struct resource *mem,
+int intel_spi_probe(struct device *dev, void __iomem *base,
 		    const struct intel_spi_boardinfo *info);
 
 #endif /* SPI_INTEL_H */