Unverified Commit 9ae27a8d authored Feb 12, 2018 by Charles Keepax Committed by Mark Brown Feb 13, 2018

regmap: Don't use format_val in regmap_bulk_read



A bulk read can be implemented either through regmap_raw_read, or
by reading each register individually using regmap_read.  Both
regmap_read and regmap_bulk_read should return values in native
endian. In the individual case the current implementation calls
format_val to put the data into the output array, which can cause
endian issues. The regmap_read will have already converted the data
into native endian, if the hosts endian differs from the device then
format_val will switch the endian back again.

Rather than using format_val simply use the code that is called if
there is no format_val function. This code supports all cases except
24-bit but there don't appear to be any users of regmap_bulk_read for
24-bit. Additionally, it would have to be a big endian host for the
old code to actually function correctly anyway.

Fixes: 15b8d2c4 ("regmap: Fix regmap_bulk_read in BE mode")
Reported-by: David Rhodes <david.rhodes@cirrus.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

parent 7928b2cb

drivers/base/regmap/regmap.c

+23 −32

Original line number	Diff line number	Diff line
		@@ -2709,22 +2709,6 @@ int regmap_bulk_read(struct regmap map, unsigned int reg, void val,
		for (i = 0; i < val_count * val_bytes; i += val_bytes)
		map->format.parse_inplace(val + i);
		} else {
		for (i = 0; i < val_count; i++) {
		unsigned int ival;
		ret = regmap_read(map, reg + regmap_get_offset(map, i),
		&ival);
		if (ret != 0)
		return ret;

		if (map->format.format_val) {
		map->format.format_val(val + (i * val_bytes), ival, 0);
		} else {
		/* Devices providing read and write
		* operations can use the bulk I/O
		* functions if they define a val_bytes,
		* we assume that the values are native
		* endian.
		*/
		#ifdef CONFIG_64BIT
		u64 *u64 = val;
		#endif
		@@ -2732,6 +2716,14 @@ int regmap_bulk_read(struct regmap map, unsigned int reg, void val,
		u16 *u16 = val;
		u8 *u8 = val;

		for (i = 0; i < val_count; i++) {
		unsigned int ival;

		ret = regmap_read(map, reg + regmap_get_offset(map, i),
		&ival);
		if (ret != 0)
		return ret;

		switch (map->format.val_bytes) {
		#ifdef CONFIG_64BIT
		case 8:
		@@ -2752,7 +2744,6 @@ int regmap_bulk_read(struct regmap map, unsigned int reg, void val,
		}
		}
		}
		}

		return 0;
		}