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charset="utf-8" X-Sendblock-Type: AUTO_CONFIDENTIAL CMS-TYPE: 102P DLP-Filter: Pass X-CFilter-Loop: Reflected X-CMS-RootMailID: 20211101114158epcas2p1d0762d52029b1b09912fd99665dd66f5 References: <20211101113819.50651-1-jaewon02.kim@samsung.com> <001001d7d153$5fb18840$1f1498c0$@samsung.com> <5b05ff2e-953c-d1a3-8347-4d3f9911cc49@canonical.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Krzysztof > On 04/11/2021 09:10, Jaewon Kim wrote: > > > >>> + if (ret) { > >>> + dev_err(dev, "usi-sysreg offset is not specified\n"); > >>> + return ret; > >>> + } > >>> + > >>> + regmap_update_bits(i2c->usi_sysreg, i2c->usi_offset, > >>> + SYSREG_USI_SW_CONF_MASK, SYSREG_I2C_SW_CONF); > >>> + > >>> + exynos_usi_reset(i2c); > >> > >> You are clearing the reset flag, but not setting it back on probe > >> failure. What happens if the probe fails after this clear()? E.g. > >> because of deferred probe? The next probe try will start on a not-reset controller. Will it work? > >> > > > > The user manual guides USI_RESET to be done after changing the system register. > > For clarity, we will change not only to clear reset, but to clear after reset. > > > > What I meant, is do you handle probe failure correctly (e.g. probe deferral)? It's fine to leave the > reset cleared after deferred probe? > I understood. In my opinion, rather than resetting USI_CON_RESET in the probe fail case. It seems it is more clear to set the reset as shown below. val = readl(i2c->regs + USI_CON); val |= USI_CON_RESET; writel(val, i2c->regs + USI_CON); udelay(1); val = readl(i2c->regs + USI_CON); val &= ~USI_CON_RESET; writel(val, i2c->regs + USI_CON); > Best regards, > Krzysztof Thanks Jaewon Kim