> -----Original Message----- > From: Krzysztof Kozlowski <k...@kernel.org> > Sent: Tuesday, December 8, 2020 12:35 AM > To: Krzysztof Kozlowski <k...@kernel.org>; linux-arm- > ker...@lists.infradead.org; linux-samsung-...@vger.kernel.org; linux- > ker...@vger.kernel.org > Cc: Sylwester Nawrocki <snawro...@kernel.org>; Marek Szyprowski > <m.szyprow...@samsung.com>; Bartlomiej Zolnierkiewicz > <b.zolnier...@samsung.com>; Arnd Bergmann <a...@arndb.de>; Chanwoo > Choi <cw00.c...@samsung.com>; Alim Akhtar <alim.akh...@samsung.com>; > Pankaj Dubey <pankaj.du...@samsung.com>; sta...@vger.kernel.org > Subject: [PATCH v2 2/4] soc: samsung: exynos-asv: handle reading revision > register error > > If regmap_read() fails, the product_id local variable will contain random value > from the stack. Do not try to parse such value and fail the ASV driver probe. > > Fixes: 5ea428595cc5 ("soc: samsung: Add Exynos Adaptive Supply Voltage > driver") > Cc: <sta...@vger.kernel.org> > Signed-off-by: Krzysztof Kozlowski <k...@kernel.org> > --- > drivers/soc/samsung/exynos-asv.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/soc/samsung/exynos-asv.c > b/drivers/soc/samsung/exynos-asv.c > index f653e3533f0f..5daeadc36382 100644 > --- a/drivers/soc/samsung/exynos-asv.c > +++ b/drivers/soc/samsung/exynos-asv.c > @@ -129,7 +129,13 @@ static int exynos_asv_probe(struct platform_device > *pdev) > return PTR_ERR(asv->chipid_regmap); > } > > - regmap_read(asv->chipid_regmap, EXYNOS_CHIPID_REG_PRO_ID, > &product_id); > + ret = regmap_read(asv->chipid_regmap, > EXYNOS_CHIPID_REG_PRO_ID, > + &product_id); > + if (ret < 0) { > + dev_err(&pdev->dev, "Cannot read revision from > ChipID: %d\n", > + ret); > + return -ENODEV; > + } > > switch (product_id & EXYNOS_MASK) { > case 0xE5422000: > -- > 2.25.1 Reviewed-by: Pankaj Dubey <pankaj.du...@samsung.com>