From: Lucas Tanure <tanure@linux.com>
To: Neil Armstrong <narmstrong@baylibre.com>,
Kevin Hilman <khilman@baylibre.com>,
Jerome Brunet <jbrunet@baylibre.com>,
Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: linux-i2c@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
linux-amlogic@lists.infradead.org, linux-kernel@vger.kernel.org,
Lucas Tanure <tanure@linux.com>
Subject: [PATCH 0/3] Ensure Low period of SCL is correct
Date: Sat, 26 Mar 2022 10:22:26 +0000 [thread overview]
Message-ID: <20220326102229.421718-1-tanure@linux.com> (raw)
The default duty cycle of 33% is less than the required
by the I2C specs for the LOW period of the SCL clock.
So, for 100Khz or less, use 50%H/50%L duty cycle, and
for the clock above 100Khz, use 40%H/60%L duty cycle.
That ensures the low period of SCL is always more than
the minimum required by the specs at any given frequency.
Lucas Tanure (3):
i2c: meson: Use _SHIFT and _MASK for register definitions
i2c: meson: Use 50% duty cycle for I2C clock
i2c: meson: Remove meson_i2c_data
drivers/i2c/busses/i2c-meson.c | 104 ++++++++++++++++++---------------
1 file changed, 56 insertions(+), 48 deletions(-)
--
2.35.1
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next reply other threads:[~2022-03-26 10:24 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-26 10:22 Lucas Tanure [this message]
2022-03-26 10:22 ` [PATCH 1/3] i2c: meson: Use _SHIFT and _MASK for register definitions Lucas Tanure
2022-03-26 10:22 ` [PATCH 2/3] i2c: meson: Use 50% duty cycle for I2C clock Lucas Tanure
2022-04-05 9:30 ` Neil Armstrong
2022-04-06 11:31 ` Neil Armstrong
2022-04-08 7:18 ` Lucas Tanure
2022-03-26 10:22 ` [PATCH 3/3] i2c: meson: Remove meson_i2c_data Lucas Tanure
2022-03-28 20:37 ` [PATCH 0/3] Ensure Low period of SCL is correct Kevin Hilman
2022-03-28 22:31 ` Lucas Tanure
2022-04-04 8:01 ` Neil Armstrong
2022-04-04 18:00 ` Vyacheslav
[not found] ` <CAJX_Q+1Y5pO_AGaFSXfo-J3EdGQeM2XYXzvsUtjtAFEXdwKEdQ@mail.gmail.com>
2022-04-05 15:11 ` Neil Armstrong
2022-04-08 7:19 ` Lucas Tanure
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