From: Thomas Petazzoni Date: Thu, 2 Aug 2018 08:56:25 +0000 (+0200) Subject: mtd: rawnand: marvell: use regmap_update_bits() for syscon access X-Git-Tag: v5.4-rc1~2439^2^2~72 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=88aa3bbfc020d14b13d67af3f5c08aa992d82cd8;p=platform%2Fkernel%2Flinux-rpi.git mtd: rawnand: marvell: use regmap_update_bits() for syscon access 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 Signed-off-by: Miquel Raynal --- diff --git a/drivers/mtd/nand/raw/marvell_nand.c b/drivers/mtd/nand/raw/marvell_nand.c index 7af4d62..f06b5c4 100644 --- a/drivers/mtd/nand/raw/marvell_nand.c +++ b/drivers/mtd/nand/raw/marvell_nand.c @@ -2697,24 +2697,23 @@ 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 |= 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 |= 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 */