From mboxrd@z Thu Jan 1 00:00:00 1970 From: cristian.birsan@microchip.com (Cristian Birsan) Date: Thu, 4 Aug 2016 17:55:58 +0300 Subject: [PATCH 2/2] regmap: debugfs: Add support for dumping write only device registers In-Reply-To: <1470322558-7501-1-git-send-email-cristian.birsan@microchip.com> References: <1470322558-7501-1-git-send-email-cristian.birsan@microchip.com> Message-ID: <1470322558-7501-3-git-send-email-cristian.birsan@microchip.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Add support for dumping write only device registers in debugfs. This is useful for audio codecs that have write only registers (like WM8731). The logic that decides if a value can be printed is moved to regmap_printable() function to allow for easier future updates. Signed-off-by: Cristian Birsan --- drivers/base/regmap/regmap-debugfs.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c index 3f0a7e2..8db10e9 100644 --- a/drivers/base/regmap/regmap-debugfs.c +++ b/drivers/base/regmap/regmap-debugfs.c @@ -77,6 +77,17 @@ static void regmap_debugfs_free_dump_cache(struct regmap *map) } } +static bool regmap_printable(struct regmap *map, unsigned int reg) +{ + if (regmap_precious(map, reg)) + return false; + + if (!regmap_readable(map, reg) && !regmap_cached(map, reg)) + return false; + + return true; +} + /* * Work out where the start offset maps into register numbers, bearing * in mind that we suppress hidden registers. @@ -105,8 +116,7 @@ static unsigned int regmap_debugfs_get_dump_start(struct regmap *map, if (list_empty(&map->debugfs_off_cache)) { for (; i <= map->max_register; i += map->reg_stride) { /* Skip unprinted registers, closing off cache entry */ - if (!regmap_readable(map, i) || - regmap_precious(map, i)) { + if (!regmap_printable(map, i)) { if (c) { c->max = p - 1; c->max_reg = i - map->reg_stride; @@ -204,7 +214,7 @@ static ssize_t regmap_read_debugfs(struct regmap *map, unsigned int from, start_reg = regmap_debugfs_get_dump_start(map, from, *ppos, &p); for (i = start_reg; i <= to; i += map->reg_stride) { - if (!regmap_readable(map, i)) + if (!regmap_readable(map, i) && !regmap_cached(map, i)) continue; if (regmap_precious(map, i)) @@ -222,7 +232,11 @@ static ssize_t regmap_read_debugfs(struct regmap *map, unsigned int from, buf_pos += map->debugfs_reg_len + 2; /* Format the value, write all X if we can't read */ - ret = regmap_read(map, i, &val); + if (regmap_readable(map, i)) + ret = regmap_read(map, i, &val); + else + ret = regcache_read(map, i, &val); + if (ret == 0) snprintf(buf + buf_pos, count - buf_pos, "%.*x", map->debugfs_val_len, val); -- 1.9.1