Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-15 00:21:59 +00:00
Code Issues Packages Projects Releases Wiki Activity

i2c: core: Allow override timing properties with 0

Browse Source 
Some drivers may allow to override properties with 0 value when defaults
are not in use, thus, replace memset() with corresponding per property
update.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Andy Shevchenko 2020-03-24 14:32:12 +02:00 committed by Wolfram Sang
parent e6282fc6f8
commit 263a5646d8
2 changed files with 18 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/i2c/busses/i2c-rcar.c
View File

@ -920,7 +920,7 @@ static int rcar_i2c_probe(struct platform_device *pdev)
struct rcar_i2c_priv *priv;
struct i2c_adapter *adap;
struct device *dev = &pdev->dev;
struct i2c_timings i2c_t;
struct i2c_timings i2c_t = { 0 };
int ret;
/* Otherwise logic will break because some bytes must always use PIO */

30
drivers/i2c/i2c-core-base.c
View File

@ -1593,23 +1593,21 @@ EXPORT_SYMBOL(i2c_del_adapter);
* @dev: The device to scan for I2C timing properties
* @t: the i2c_timings struct to be filled with values
* @use_defaults: bool to use sane defaults derived from the I2C specification
* when properties are not found, otherwise use 0
* when properties are not found, otherwise don't update
*
* Scan the device for the generic I2C properties describing timing parameters
* for the signal and fill the given struct with the results. If a property was
* not found and use_defaults was true, then maximum timings are assumed which
* are derived from the I2C specification. If use_defaults is not used, the
* results will be 0, so drivers can apply their own defaults later. The latter
* is mainly intended for avoiding regressions of existing drivers which want
* to switch to this function. New drivers almost always should use the defaults.
* results will be as before, so drivers can apply their own defaults before
* calling this helper. The latter is mainly intended for avoiding regressions
* of existing drivers which want to switch to this function. New drivers
* almost always should use the defaults.
*/
void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults)
{
int ret;
memset(t, 0, sizeof(*t));
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;
@ -1632,19 +1630,25 @@ void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_de
t->scl_fall_ns = 120;
}
device_property_read_u32(dev, "i2c-scl-internal-delay-ns", &t->scl_int_delay_ns);
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;
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;
device_property_read_u32(dev, "i2c-sda-hold-time-ns", &t->sda_hold_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;
device_property_read_u32(dev, "i2c-digital-filter-width-ns",
&t->digital_filter_width_ns);
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;
device_property_read_u32(dev, "i2c-analog-filter-cutoff-frequency",
&t->analog_filter_cutoff_freq_hz);
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;
}
EXPORT_SYMBOL_GPL(i2c_parse_fw_timings);