From: Wolfram Sang <wsa+renesas@sang-engineering.com>
To: linux-i2c@vger.kernel.org
Cc: linux-renesas-soc@vger.kernel.org,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Wolfram Sang <wsa+renesas@sang-engineering.com>
Subject: [RFC PATCH] i2c: refactor parsing of timings
Date: Thu, 26 Mar 2020 11:16:47 +0100 [thread overview]
Message-ID: <20200326101647.1756-1-wsa+renesas@sang-engineering.com> (raw)
When I wanted to print the chosen values to debug output, I concluded
that a helper function to parse one timing would be helpful.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
I am not entirely happy because 'dev' and 'u' is the same for each call.
Then again, we can't use a for-loop over an array of parameters, because
some default values depend on previously obtained timings.
Looking for opinions here...
drivers/i2c/i2c-core-base.c | 78 ++++++++++++++++++-------------------
1 file changed, 38 insertions(+), 40 deletions(-)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 474baaf8c9e7..60b0aa246af2 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -1609,6 +1609,18 @@ void i2c_del_adapter(struct i2c_adapter *adap)
}
EXPORT_SYMBOL(i2c_del_adapter);
+static void i2c_parse_timing(struct device *dev, char *prop_name, u32 *cur_val_p,
+ u32 def_val, bool use_def)
+{
+ int ret;
+
+ ret = device_property_read_u32(dev, prop_name, cur_val_p);
+ if (ret && use_def)
+ *cur_val_p = def_val;
+
+ dev_dbg(dev, "%s: %u\n", prop_name, *cur_val_p);
+}
+
/**
* i2c_parse_fw_timings - get I2C related timing parameters from firmware
* @dev: The device to scan for I2C timing properties
@@ -1627,49 +1639,35 @@ EXPORT_SYMBOL(i2c_del_adapter);
*/
void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults)
{
- int ret;
-
- ret = device_property_read_u32(dev, "clock-frequency", &t->bus_freq_hz);
- if (ret && use_defaults)
- t->bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ;
-
- ret = device_property_read_u32(dev, "i2c-scl-rising-time-ns", &t->scl_rise_ns);
- if (ret && use_defaults) {
- if (t->bus_freq_hz <= I2C_MAX_STANDARD_MODE_FREQ)
- t->scl_rise_ns = 1000;
- else if (t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ)
- t->scl_rise_ns = 300;
- else
- t->scl_rise_ns = 120;
- }
-
- ret = device_property_read_u32(dev, "i2c-scl-falling-time-ns", &t->scl_fall_ns);
- if (ret && use_defaults) {
- if (t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ)
- t->scl_fall_ns = 300;
- else
- t->scl_fall_ns = 120;
- }
+ bool u = use_defaults;
+ u32 d;
- ret = device_property_read_u32(dev, "i2c-scl-internal-delay-ns", &t->scl_int_delay_ns);
- if (ret && use_defaults)
- t->scl_int_delay_ns = 0;
+ i2c_parse_timing(dev, "clock-frequency", &t->bus_freq_hz,
+ I2C_MAX_STANDARD_MODE_FREQ, u);
- ret = device_property_read_u32(dev, "i2c-sda-falling-time-ns", &t->sda_fall_ns);
- if (ret && use_defaults)
- t->sda_fall_ns = t->scl_fall_ns;
-
- ret = device_property_read_u32(dev, "i2c-sda-hold-time-ns", &t->sda_hold_ns);
- if (ret && use_defaults)
- t->sda_hold_ns = 0;
-
- ret = device_property_read_u32(dev, "i2c-digital-filter-width-ns", &t->digital_filter_width_ns);
- if (ret && use_defaults)
- t->digital_filter_width_ns = 0;
+ if (t->bus_freq_hz <= I2C_MAX_STANDARD_MODE_FREQ)
+ d = 1000;
+ else if (t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ)
+ d = 300;
+ else
+ d = 120;
+ i2c_parse_timing(dev, "i2c-scl-rising-time-ns", &t->scl_rise_ns, d, u);
- ret = device_property_read_u32(dev, "i2c-analog-filter-cutoff-frequency", &t->analog_filter_cutoff_freq_hz);
- if (ret && use_defaults)
- t->analog_filter_cutoff_freq_hz = 0;
+ if (t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ)
+ d = 300;
+ else
+ d = 120;
+ i2c_parse_timing(dev, "i2c-scl-falling-time-ns", &t->scl_fall_ns, d, u);
+
+ i2c_parse_timing(dev, "i2c-scl-internal-delay-ns",
+ &t->scl_int_delay_ns, 0, u);
+ i2c_parse_timing(dev, "i2c-sda-falling-time-ns", &t->sda_fall_ns,
+ t->scl_fall_ns, u);
+ i2c_parse_timing(dev, "i2c-sda-hold-time-ns", &t->sda_hold_ns, 0, u);
+ i2c_parse_timing(dev, "i2c-digital-filter-width-ns",
+ &t->digital_filter_width_ns, 0, u);
+ i2c_parse_timing(dev, "i2c-analog-filter-cutoff-frequency",
+ &t->analog_filter_cutoff_freq_hz, 0, u);
}
EXPORT_SYMBOL_GPL(i2c_parse_fw_timings);
--
2.20.1
next reply other threads:[~2020-03-26 10:16 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-26 10:16 Wolfram Sang [this message]
2020-03-26 10:36 ` [RFC PATCH] i2c: refactor parsing of timings Geert Uytterhoeven
2020-03-26 10:50 ` Andy Shevchenko
2020-03-26 10:52 ` Wolfram Sang
2020-03-26 11:15 ` Geert Uytterhoeven
2020-03-26 12:05 ` Andy Shevchenko
2020-03-26 10:47 ` Andy Shevchenko
2020-03-26 11:00 ` Wolfram Sang
2020-03-26 11:16 ` Andy Shevchenko
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