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([82.78.167.153]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3ee141e9cf7sm23617713f8f.12.2025.09.23.07.18.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Sep 2025 07:18:33 -0700 (PDT) From: Claudiu X-Google-Original-From: Claudiu To: chris.brandt@renesas.com, andi.shyti@kernel.org, wsa@kernel.org Cc: claudiu.beznea@tuxon.dev, linux-renesas-soc@vger.kernel.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Claudiu Beznea Subject: [PATCH] i2c: riic: Allow setting frequencies lower than 50KHz Date: Tue, 23 Sep 2025 17:18:26 +0300 Message-ID: <20250923141826.3765925-1-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Claudiu Beznea The MR1.CKS field is 3 bits wide and all the possible values (from 0 to 7) are valid. This is true for all the SoCs currently integrated in upstream Linux. Take into account CKS=3D7 which allows setting bus frequencies lower than 50KHz. This may be useful at least for debugging. Fixes: d982d6651419 ("i2c: riic: remove clock and frequency restrictions") Signed-off-by: Claudiu Beznea --- drivers/i2c/busses/i2c-riic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-riic.c b/drivers/i2c/busses/i2c-riic.c index 9c164a4b9bb9..b0ee9ac45a97 100644 --- a/drivers/i2c/busses/i2c-riic.c +++ b/drivers/i2c/busses/i2c-riic.c @@ -386,7 +386,7 @@ static int riic_init_hw(struct riic_dev *riic) */ total_ticks =3D DIV_ROUND_UP(rate, t->bus_freq_hz ?: 1); =20 - for (cks =3D 0; cks < 7; cks++) { + for (cks =3D 0; cks <=3D 7; cks++) { /* * 60% low time must be less than BRL + 2 + 1 * BRL max register value is 0x1F. --=20 2.43.0