Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 5ef1ecf0 authored by Heiner Kallweit's avatar Heiner Kallweit Committed by Ulf Hansson
Browse files

mmc: sdio: fix alignment issue in struct sdio_func 



Certain 64-bit systems (e.g. Amlogic Meson GX) require buffers to be
used for DMA to be 8-byte-aligned. struct sdio_func has an embedded
small DMA buffer not meeting this requirement.
When testing switching to descriptor chain mode in meson-gx driver
SDIO is broken therefore. Fix this by allocating the small DMA buffer
separately as kmalloc ensures that the returned memory area is
properly aligned for every basic data type.

Signed-off-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Tested-by: default avatarHelmut Klein <hgkr.klein@gmail.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 4f7d029b

drivers/mmc/core/sdio_bus.c

+11 −1
Original line number Diff line number Diff line
@@ -267,7 +267,7 @@ static void sdio_release_func(struct device *dev) 
	sdio_free_func_cis(func);



	kfree(func->info);



	kfree(func->tmpbuf);

	kfree(func);

}
@@ -282,6 +282,16 @@ struct sdio_func *sdio_alloc_func(struct mmc_card *card) 
	if (!func)

		return ERR_PTR(-ENOMEM);



	/*

	 * allocate buffer separately to make sure it's properly aligned for

	 * DMA usage (incl. 64 bit DMA)

	 */

	func->tmpbuf = kmalloc(4, GFP_KERNEL);

	if (!func->tmpbuf) {

		kfree(func);

		return ERR_PTR(-ENOMEM);

	}



	func->card = card;



	device_initialize(&func->dev);

include/linux/mmc/sdio_func.h

+1 −1
Original line number Diff line number Diff line
@@ -53,7 +53,7 @@ struct sdio_func { 
	unsigned int		state;		/* function state */

#define SDIO_STATE_PRESENT	(1<<0)		/* present in sysfs */



	u8			tmpbuf[4];	/* DMA:able scratch buffer */

	u8			*tmpbuf;	/* DMA:able scratch buffer */



	unsigned		num_info;	/* number of info strings */

	const char		**info;		/* info strings */