From: Marcus Folkesson <marcus.folkesson@gmail.com>
To: Wolfram Sang <wsa+renesas@sang-engineering.com>,
Peter Rosin <peda@axentia.se>,
Michael Hennerich <michael.hennerich@analog.com>,
Bartosz Golaszewski <brgl@bgdev.pl>,
Andi Shyti <andi.shyti@kernel.org>
Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
Marcus Folkesson <marcus.folkesson@gmail.com>,
Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Subject: [PATCH v3 3/5] i2c: davinci: calculate bus freq from Hz instead of kHz
Date: Mon, 20 Oct 2025 09:17:26 +0200 [thread overview]
Message-ID: <20251020-i2c-mux-v3-3-908ac5cf9223@gmail.com> (raw)
In-Reply-To: <20251020-i2c-mux-v3-0-908ac5cf9223@gmail.com>
The bus frequency is unnecessarily converted between Hz and kHz in
several places.
This is probably an old legacy from the old times (pre-devicetrees)
when the davinci_i2c_platform_data took the bus_freq in kHz.
Stick to Hz.
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
---
drivers/i2c/busses/i2c-davinci.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 6a3d4e9e07f45ecc228943e877cde1fd9d72e8cb..82f295619c4d0ef108c57d13c10004aa25014cbf 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -117,8 +117,6 @@
/* timeout for pm runtime autosuspend */
#define DAVINCI_I2C_PM_TIMEOUT 1000 /* ms */
-#define DAVINCI_I2C_DEFAULT_BUS_FREQ 100
-
struct davinci_i2c_dev {
struct device *dev;
void __iomem *base;
@@ -134,8 +132,8 @@ struct davinci_i2c_dev {
#ifdef CONFIG_CPU_FREQ
struct notifier_block freq_transition;
#endif
- /* standard bus frequency (kHz) */
- unsigned int bus_freq;
+ /* standard bus frequency */
+ unsigned int bus_freq_hz;
/* Chip has a ICPFUNC register */
bool has_pfunc;
};
@@ -209,16 +207,16 @@ static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev)
if (device_is_compatible(dev->dev, "ti,keystone-i2c"))
d = 6;
- clk = ((input_clock / (psc + 1)) / (dev->bus_freq * 1000));
+ clk = ((input_clock / (psc + 1)) / (dev->bus_freq_hz));
/* Avoid driving the bus too fast because of rounding errors above */
- if (input_clock / (psc + 1) / clk > dev->bus_freq * 1000)
+ if (input_clock / (psc + 1) / clk > dev->bus_freq_hz)
clk++;
/*
* According to I2C-BUS Spec 2.1, in FAST-MODE LOW period should be at
* least 1.3uS, which is not the case with 50% duty cycle. Driving HIGH
* to LOW ratio as 1 to 2 is more safe.
*/
- if (dev->bus_freq > 100)
+ if (dev->bus_freq_hz > 100000)
clkl = (clk << 1) / 3;
else
clkl = (clk >> 1);
@@ -269,7 +267,7 @@ static int i2c_davinci_init(struct davinci_i2c_dev *dev)
davinci_i2c_read_reg(dev, DAVINCI_I2C_CLKL_REG));
dev_dbg(dev->dev, "CLKH = %d\n",
davinci_i2c_read_reg(dev, DAVINCI_I2C_CLKH_REG));
- dev_dbg(dev->dev, "bus_freq = %dkHz\n", dev->bus_freq);
+ dev_dbg(dev->dev, "bus_freq_hz = %dHz\n", dev->bus_freq_hz);
/* Take the I2C module out of reset: */
@@ -761,9 +759,9 @@ static int davinci_i2c_probe(struct platform_device *pdev)
r = device_property_read_u32(&pdev->dev, "clock-frequency", &prop);
if (r)
- prop = DAVINCI_I2C_DEFAULT_BUS_FREQ;
+ prop = I2C_MAX_STANDARD_MODE_FREQ;
- dev->bus_freq = prop / 1000;
+ dev->bus_freq_hz = prop;
dev->has_pfunc = device_property_present(&pdev->dev, "ti,has-pfunc");
--
2.50.1
next prev parent reply other threads:[~2025-10-20 7:18 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-20 7:17 [PATCH v3 0/5] I2C Mux per channel bus speed Marcus Folkesson
2025-10-20 7:17 ` [PATCH v3 1/5] i2c: core: add callback to change bus frequency Marcus Folkesson
2025-10-20 7:17 ` [PATCH v3 2/5] i2c: mux: add support for per channel " Marcus Folkesson
2025-10-20 7:17 ` Marcus Folkesson [this message]
2025-10-20 7:17 ` [PATCH v3 4/5] i2c: davinci: add support for setting " Marcus Folkesson
2025-10-20 7:17 ` [PATCH v3 5/5] docs: i2c: i2c-topology: add section about bus speed Marcus Folkesson
2025-11-10 9:06 ` [PATCH v3 0/5] I2C Mux per channel " Marcus Folkesson
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