On Wed, Nov 09, 2016 at 06:16:13PM +0100, Clemens Gruber wrote: > Support setting the reference voltage from the device tree. > > Signed-off-by: Clemens Gruber <clemens.gru...@pqgruber.com> > --- > drivers/hwmon/mcp3021.c | 46 ++++++++++++++++++++++++++++++++++++---------- > 1 file changed, 36 insertions(+), 10 deletions(-) > > diff --git a/drivers/hwmon/mcp3021.c b/drivers/hwmon/mcp3021.c > index 972444a..81f4b7f 100644 > --- a/drivers/hwmon/mcp3021.c > +++ b/drivers/hwmon/mcp3021.c > @@ -4,6 +4,7 @@ > * Copyright (C) 2008-2009, 2012 Freescale Semiconductor, Inc. > * Author: Mingkai Hu <mingkai...@freescale.com> > * Reworked by Sven Schuchmann <schuchm...@schleissheimer.de> > + * Copyright (C) 2016 Clemens Gruber <clemens.gru...@pqgruber.com>
Sorry, I can't accept that for such a minor change. Feel free to add something like "devicetree support added by ...", if you like. > * > * This driver export the value of analog input voltage to sysfs, the > * voltage unit is mV. Through the sysfs interface, lm-sensors tool > @@ -22,11 +23,13 @@ > #include <linux/i2c.h> > #include <linux/err.h> > #include <linux/device.h> > +#include <linux/of.h> > +#include <linux/of_device.h> > > -/* Vdd info */ > +/* Vdd / reference voltage in millivolt */ > #define MCP3021_VDD_MAX 5500 > #define MCP3021_VDD_MIN 2700 > -#define MCP3021_VDD_REF 3300 > +#define MCP3021_VDD_DEFAULT 3300 I don't really see the value of changing this, but if it makes you feel better at least make it MCP3021_VDD_REF_DEFAULT. > > /* output format */ > #define MCP3021_SAR_SHIFT 2 > @@ -47,7 +50,7 @@ enum chips { > */ > struct mcp3021_data { > struct device *hwmon_dev; > - u32 vdd; /* device power supply */ > + u32 vdd; /* supply and reference voltage in millivolt */ > u16 sar_shift; > u16 sar_mask; > u8 output_res; > @@ -106,6 +109,7 @@ static int mcp3021_probe(struct i2c_client *client, > { > int err; > struct mcp3021_data *data = NULL; > + struct device_node *np = client->dev.of_node; > > if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) > return -ENODEV; > @@ -117,6 +121,21 @@ static int mcp3021_probe(struct i2c_client *client, > > i2c_set_clientdata(client, data); > > + if (np) { > + if (of_property_read_u32(np, "reference-voltage-microvolt", > + &data->vdd)) > + data->vdd = MCP3021_VDD_DEFAULT; > + else > + data->vdd /= 1000; It would be slightly better to reverse the logic here to make the code easier to read. if (!of_property_read_u32(np, "reference-voltage-microvolt", &data->vdd)) data->vdd /= 1000; else data->vdd = MCP3021_VDD_DEFAULT; Not worth arguing about it, though, so feel free to keep it as is. > + } else { > + u32 *pdata = dev_get_platdata(&client->dev); > + > + if (pdata) > + data->vdd = *pdata; > + else > + data->vdd = MCP3021_VDD_DEFAULT; > + } > + > switch (id->driver_data) { > case mcp3021: > data->sar_shift = MCP3021_SAR_SHIFT; > @@ -129,15 +148,12 @@ static int mcp3021_probe(struct i2c_client *client, > data->sar_mask = MCP3221_SAR_MASK; > data->output_res = MCP3221_OUTPUT_RES; > break; > + default: > + return -ENODEV; Hmm ... that is really an unrelated change (nor is it really needed unless there is a bug in the code). Not worth arguing about it either, but please keep in mind that this is one of the things making life hard for maintainers. > } > > - if (dev_get_platdata(&client->dev)) { > - data->vdd = *(u32 *)dev_get_platdata(&client->dev); > - if (data->vdd > MCP3021_VDD_MAX || data->vdd < MCP3021_VDD_MIN) > - return -EINVAL; > - } else { > - data->vdd = MCP3021_VDD_REF; > - } > + if (data->vdd > MCP3021_VDD_MAX || data->vdd < MCP3021_VDD_MIN) > + return -EINVAL; > > err = sysfs_create_file(&client->dev.kobj, &dev_attr_in0_input.attr); > if (err) > @@ -173,9 +189,19 @@ static const struct i2c_device_id mcp3021_id[] = { > }; > MODULE_DEVICE_TABLE(i2c, mcp3021_id); > > +#ifdef CONFIG_OF > +static const struct of_device_id of_mcp3021_match[] = { > + { .compatible = "microchip,mcp3021", .data = (void *)mcp3021 }, > + { .compatible = "microchip,mcp3221", .data = (void *)mcp3221 }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, of_mcp3021_match); > +#endif > + > static struct i2c_driver mcp3021_driver = { > .driver = { > .name = "mcp3021", > + .of_match_table = of_match_ptr(of_mcp3021_match), > }, > .probe = mcp3021_probe, > .remove = mcp3021_remove, > -- > 2.10.2 >