lkml.org 
[lkml]   [2019]   [Nov]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH AUTOSEL 4.19 080/205] mtd: rawnand: marvell: use regmap_update_bits() for syscon access
Date
From: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

[ Upstream commit 88aa3bbfc020d14b13d67af3f5c08aa992d82cd8 ]

The marvell_nfc_init() function fiddles with some bits of a system
controller on Armada 7K/8K. However, it does a read/modify/write
sequence on GENCONF_CLK_GATING_CTRL and GENCONF_ND_CLK_CTRL, which
isn't safe from a concurrency point of view, as the regmap lock isn't
taken accross the read/modify/write sequence. To solve this issue, use
regmap_update_bits().

While at it, since the "reg" variable is no longer needed for the
read/modify/write sequences, get rid of it for the regmap_write() to
GENCONF_SOC_DEVICE_MUX, and directly pass the value to be written as
argument.

Fixes: 02f26ecf8c772 ("mtd: nand: add reworked Marvell NAND controller driver")
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/mtd/nand/raw/marvell_nand.c | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/mtd/nand/raw/marvell_nand.c b/drivers/mtd/nand/raw/marvell_nand.c
index 9c90695a885fe..7a84a8f05b46d 100644
--- a/drivers/mtd/nand/raw/marvell_nand.c
+++ b/drivers/mtd/nand/raw/marvell_nand.c
@@ -2710,24 +2710,23 @@ static int marvell_nfc_init(struct marvell_nfc *nfc)
struct regmap *sysctrl_base =
syscon_regmap_lookup_by_phandle(np,
"marvell,system-controller");
- u32 reg;

if (IS_ERR(sysctrl_base))
return PTR_ERR(sysctrl_base);

- reg = GENCONF_SOC_DEVICE_MUX_NFC_EN |
- GENCONF_SOC_DEVICE_MUX_ECC_CLK_RST |
- GENCONF_SOC_DEVICE_MUX_ECC_CORE_RST |
- GENCONF_SOC_DEVICE_MUX_NFC_INT_EN;
- regmap_write(sysctrl_base, GENCONF_SOC_DEVICE_MUX, reg);
+ regmap_write(sysctrl_base, GENCONF_SOC_DEVICE_MUX,
+ GENCONF_SOC_DEVICE_MUX_NFC_EN |
+ GENCONF_SOC_DEVICE_MUX_ECC_CLK_RST |
+ GENCONF_SOC_DEVICE_MUX_ECC_CORE_RST |
+ GENCONF_SOC_DEVICE_MUX_NFC_INT_EN);

- regmap_read(sysctrl_base, GENCONF_CLK_GATING_CTRL, &reg);
- reg |= GENCONF_CLK_GATING_CTRL_ND_GATE;
- regmap_write(sysctrl_base, GENCONF_CLK_GATING_CTRL, reg);
+ regmap_update_bits(sysctrl_base, GENCONF_CLK_GATING_CTRL,
+ GENCONF_CLK_GATING_CTRL_ND_GATE,
+ GENCONF_CLK_GATING_CTRL_ND_GATE);

- regmap_read(sysctrl_base, GENCONF_ND_CLK_CTRL, &reg);
- reg |= GENCONF_ND_CLK_CTRL_EN;
- regmap_write(sysctrl_base, GENCONF_ND_CLK_CTRL, reg);
+ regmap_update_bits(sysctrl_base, GENCONF_ND_CLK_CTRL,
+ GENCONF_ND_CLK_CTRL_EN,
+ GENCONF_ND_CLK_CTRL_EN);
}

/* Configure the DMA if appropriate */
--
2.20.1
\
 
 \ /
  Last update: 2019-11-08 13:10    [W:0.494 / U:1.924 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site