DMA-API: dcdbas: update DMA mask handing

dcdbas was explicitly initializing DMA masks thusly:
	dcdbas_pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
	dcdbas_pdev->dev.dma_mask = &dcdbas_pdev->dev.coherent_dma_mask;
which bypasses the architecture check.  Moreover, it is creating the
dcdbas_pdev device itself, and using the platform_device_register_full()
avoids some of this explicit initialization.

Convert the driver to use platform_device_register_full(), and as it
makes use of coherent DMA, also call dma_set_coherent_mask() to ensure
that the architecture gets to check the mask.

Tested-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/drivers/firmware/dcdbas.c b/drivers/firmware/dcdbas.c
index ff080ee201973bd3c76513d11d36273d70971e59..1b5e8e46226d5f3d6bebdb770d8b29de9f04fc43 100644 (file)
--- a/drivers/firmware/dcdbas.c
+++ b/drivers/firmware/dcdbas.c
@@ -545,12 +545,15 @@ static int dcdbas_probe(struct platform_device *dev)
        host_control_action = HC_ACTION_NONE;
        host_control_smi_type = HC_SMITYPE_NONE;
 
+       dcdbas_pdev = dev;
+
        /*
         * BIOS SMI calls require buffer addresses be in 32-bit address space.
         * This is done by setting the DMA mask below.
         */
-       dcdbas_pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
-       dcdbas_pdev->dev.dma_mask = &dcdbas_pdev->dev.coherent_dma_mask;
+       error = dma_set_coherent_mask(&dcdbas_pdev->dev, DMA_BIT_MASK(32));
+       if (error)
+               return error;
 
        error = sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group);
        if (error)
@@ -581,6 +584,14 @@ static struct platform_driver dcdbas_driver = {
        .remove         = dcdbas_remove,
 };
 
+static const struct platform_device_info dcdbas_dev_info __initdata = {
+       .name           = DRIVER_NAME,
+       .id             = -1,
+       .dma_mask       = DMA_BIT_MASK(32),
+};
+
+static struct platform_device *dcdbas_pdev_reg;
+
 /**
  * dcdbas_init: initialize driver
  */
@@ -592,20 +603,14 @@ static int __init dcdbas_init(void)
        if (error)
                return error;
 
-       dcdbas_pdev = platform_device_alloc(DRIVER_NAME, -1);
-       if (!dcdbas_pdev) {
-               error = -ENOMEM;
+       dcdbas_pdev_reg = platform_device_register_full(&dcdbas_dev_info);
+       if (IS_ERR(dcdbas_pdev_reg)) {
+               error = PTR_ERR(dcdbas_pdev_reg);
                goto err_unregister_driver;
        }
 
-       error = platform_device_add(dcdbas_pdev);
-       if (error)
-               goto err_free_device;
-
        return 0;
 
- err_free_device:
-       platform_device_put(dcdbas_pdev);
  err_unregister_driver:
        platform_driver_unregister(&dcdbas_driver);
        return error;
@@ -628,8 +633,9 @@ static void __exit dcdbas_exit(void)
         * all sysfs attributes belonging to this module have been
         * released.
         */
-       smi_data_buf_free();
-       platform_device_unregister(dcdbas_pdev);
+       if (dcdbas_pdev)
+               smi_data_buf_free();
+       platform_device_unregister(dcdbas_pdev_reg);
        platform_driver_unregister(&dcdbas_driver);
 }