From: Alexander Sverdlin <alexander.sverdlin@nokia.com>
To: linux-i2c@vger.kernel.org
Cc: Sekhar Nori <nsekhar@ti.com>,
Alexander Sverdlin <alexander.sverdlin@nokia.com>,
linux-arm-kernel@lists.infradead.org,
Kevin Hilman <khilman@kernel.org>
Subject: [PATCH] i2c: davinci: Avoid zero value of CLKH
Date: Fri, 13 Jul 2018 17:20:17 +0200 [thread overview]
Message-ID: <20180713152017.2207-1-alexander.sverdlin@nokia.com> (raw)
If CLKH is set to 0 I2C clock is not generated at all, so avoid this value
and stretch the clock in this case.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
---
drivers/i2c/busses/i2c-davinci.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 75d6ab177055..7379043711df 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -237,12 +237,16 @@ static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev)
/*
* It's not always possible to have 1 to 2 ratio when d=7, so fall back
* to minimal possible clkh in this case.
+ *
+ * Note:
+ * CLKH is not allowed to be 0, in this case I2C clock is not generated
+ * at all
*/
- if (clk >= clkl + d) {
+ if (clk > clkl + d) {
clkh = clk - clkl - d;
clkl -= d;
} else {
- clkh = 0;
+ clkh = 1;
clkl = clk - (d << 1);
}
--
2.18.0
next reply other threads:[~2018-07-13 15:20 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-13 15:20 Alexander Sverdlin [this message]
2018-07-17 11:57 ` [PATCH] i2c: davinci: Avoid zero value of CLKH Sekhar Nori
2018-07-20 18:43 ` Grygorii Strashko
2018-07-20 22:18 ` Wolfram Sang
2018-07-23 18:07 ` Wolfram Sang
2018-07-24 6:17 ` Sekhar Nori
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