[PATCH 1/2] new helper to create platform devices with dma mask
Uwe Kleine-König
u.kleine-koenig at pengutronix.de
Thu Aug 25 05:16:00 EDT 2011
compared to the most powerful and already existing helper (namely
platform_device_register_resndata) this allows to specify a dma_mask.
To make eventual extensions later more easy, a struct holding the used
information is created instead of passing the information by function
parameters.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
---
Hello,
as this changes how the parameters are passed, this patch has an impact
on code size for the calling sites. On ARCH=arm/mx27_defconfig it
results in bloat-o-meter reporting:
add/remove: 3/3 grow/shrink: 4/0 up/down: 354/-170 (184)
function old new delta
platform_device_register_full - 216 +216
imx_add_imx_dma 56 88 +32
__kstrtab_platform_device_register_full - 30 +30
imx_add_imx_sdma 132 160 +28
alarmtimer_init 312 336 +24
mxc_register_gpio 156 172 +16
__ksymtab_platform_device_register_full - 8 +8
__ksymtab_platform_device_register_resndata 8 - -8
__kstrtab_platform_device_register_resndata 34 - -34
platform_device_register_resndata 128 - -128
So calling the already existing functions is a bit more expensive.
With the second patch applied the maximal increase for a call site is
+36.
Still I think using the struct is better than a function with 8
parameters.
Best regards
Uwe
drivers/base/platform.c | 52 ++++++++++++++++++++++++---------------
include/linux/platform_device.h | 48 ++++++++++++++++++++++++++++++++++-
2 files changed, 78 insertions(+), 22 deletions(-)
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 0cad9c7..691a1a0 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -375,52 +375,64 @@ void platform_device_unregister(struct platform_device *pdev)
EXPORT_SYMBOL_GPL(platform_device_unregister);
/**
- * platform_device_register_resndata - add a platform-level device with
+ * platform_device_register_full - add a platform-level device with
* resources and platform-specific data
*
- * @parent: parent device for the device we're adding
- * @name: base name of the device we're adding
- * @id: instance id
- * @res: set of resources that needs to be allocated for the device
- * @num: number of resources
- * @data: platform specific data for this platform device
- * @size: size of platform specific data
+ * @pdevinfo: data used to create device
*
* Returns &struct platform_device pointer on success, or ERR_PTR() on error.
*/
-struct platform_device *platform_device_register_resndata(
- struct device *parent,
- const char *name, int id,
- const struct resource *res, unsigned int num,
- const void *data, size_t size)
+struct platform_device *platform_device_register_full(
+ struct platform_device_info *pdevinfo)
{
int ret = -ENOMEM;
struct platform_device *pdev;
- pdev = platform_device_alloc(name, id);
+ pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
if (!pdev)
- goto err;
-
- pdev->dev.parent = parent;
+ goto err_alloc;
+
+ pdev->dev.parent = pdevinfo->parent;
+
+ if (pdevinfo->dma_mask) {
+ /*
+ * This memory isn't freed when the device is put,
+ * I don't have a nice idea for that though. Conceptually
+ * dma_mask in struct device should not be a pointer.
+ * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
+ */
+ pdev->dev.dma_mask =
+ kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
+ if (!pdev->dev.dma_mask)
+ goto err;
+
+ *pdev->dev.dma_mask = pdevinfo->dma_mask;
+ pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
+ }
- ret = platform_device_add_resources(pdev, res, num);
+ ret = platform_device_add_resources(pdev,
+ pdevinfo->res, pdevinfo->num_res);
if (ret)
goto err;
- ret = platform_device_add_data(pdev, data, size);
+ ret = platform_device_add_data(pdev,
+ pdevinfo->data, pdevinfo->size_data);
if (ret)
goto err;
ret = platform_device_add(pdev);
if (ret) {
err:
+ kfree(pdev->dev.dma_mask);
+
+err_alloc:
platform_device_put(pdev);
return ERR_PTR(ret);
}
return pdev;
}
-EXPORT_SYMBOL_GPL(platform_device_register_resndata);
+EXPORT_SYMBOL_GPL(platform_device_register_full);
static int platform_drv_probe(struct device *_dev)
{
diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
index 27bb05a..651a066 100644
--- a/include/linux/platform_device.h
+++ b/include/linux/platform_device.h
@@ -49,10 +49,54 @@ extern struct resource *platform_get_resource_byname(struct platform_device *, u
extern int platform_get_irq_byname(struct platform_device *, const char *);
extern int platform_add_devices(struct platform_device **, int);
-extern struct platform_device *platform_device_register_resndata(
+struct platform_device_info {
+ struct device *parent;
+
+ const char *name;
+ int id;
+
+ const struct resource *res;
+ unsigned int num_res;
+
+ const void *data;
+ size_t size_data;
+ u64 dma_mask;
+};
+extern struct platform_device *platform_device_register_full(
+ struct platform_device_info *pdevinfo);
+
+/**
+ * platform_device_register_resndata - add a platform-level device with
+ * resources and platform-specific data
+ *
+ * @parent: parent device for the device we're adding
+ * @name: base name of the device we're adding
+ * @id: instance id
+ * @res: set of resources that needs to be allocated for the device
+ * @num: number of resources
+ * @data: platform specific data for this platform device
+ * @size: size of platform specific data
+ *
+ * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
+ */
+static inline struct platform_device *platform_device_register_resndata(
struct device *parent, const char *name, int id,
const struct resource *res, unsigned int num,
- const void *data, size_t size);
+ const void *data, size_t size) {
+
+ struct platform_device_info pdevinfo = {
+ .parent = parent,
+ .name = name,
+ .id = id,
+ .res = res,
+ .num_res = num,
+ .data = data,
+ .size_data = size,
+ .dma_mask = 0,
+ };
+
+ return platform_device_register_full(&pdevinfo);
+}
/**
* platform_device_register_simple - add a platform-level device and its resources
--
1.7.5.4
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