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Mon, 30 Nov 2020 03:13:44 -0800 (PST) Date: Mon, 30 Nov 2020 19:13:40 +0800 From: Ikjoon Jang To: Crystal Guo Subject: Re: [v6, 3/3] reset-controller: ti: force the write operation when assert or deassert Message-ID: <20201130111340.GA3042402@chromium.org> References: <20200930022159.5559-1-crystal.guo@mediatek.com> <20200930022159.5559-4-crystal.guo@mediatek.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200930022159.5559-4-crystal.guo@mediatek.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201130_061347_245521_C29582BD X-CRM114-Status: GOOD ( 19.32 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, yong.liang@mediatek.com, s-anna@ti.com, srv_heupstream@mediatek.com, seiya.wang@mediatek.com, linux-kernel@vger.kernel.org, fan.chen@mediatek.com, robh+dt@kernel.org, linux-mediatek@lists.infradead.org, p.zabel@pengutronix.de, matthias.bgg@gmail.com, yingjoe.chen@mediatek.com, stanley.chu@mediatek.com, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Wed, Sep 30, 2020 at 10:21:59AM +0800, Crystal Guo wrote: > Force the write operation in case the read already happens > to return the correct value. > > Signed-off-by: Crystal Guo > --- > drivers/reset/reset-ti-syscon.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/reset/reset-ti-syscon.c b/drivers/reset/reset-ti-syscon.c > index 5d1f8306cd4f..c34394f1e9e2 100644 > --- a/drivers/reset/reset-ti-syscon.c > +++ b/drivers/reset/reset-ti-syscon.c > @@ -97,7 +97,7 @@ static int ti_syscon_reset_assert(struct reset_controller_dev *rcdev, > mask = BIT(control->assert_bit); > value = (control->flags & ASSERT_SET) ? mask : 0x0; > > - return regmap_update_bits(data->regmap, control->assert_offset, mask, value); > + return regmap_write_bits(data->regmap, control->assert_offset, mask, value); > } I don't think there are no reset controllers with cached regmap, thus I don't think this is needed. Are there any specific reasons behind this, what I've missed here? We need to be sure that all other devices using this driver should have no side effects on write. I can think of a weird controller doing unwanted things internally on every write disregarding the current state. (or is this overly paranoid?) > > /** > @@ -128,7 +128,7 @@ static int ti_syscon_reset_deassert(struct reset_controller_dev *rcdev, > mask = BIT(control->deassert_bit); > value = (control->flags & DEASSERT_SET) ? mask : 0x0; > > - return regmap_update_bits(data->regmap, control->deassert_offset, mask, value); > + return regmap_write_bits(data->regmap, control->deassert_offset, mask, value); > } > > /** _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek