On Fri, Sep 20, 2013 at 11:15:29AM -0700, Guenter Roeck wrote: > On Fri, Sep 20, 2013 at 10:39:17AM -0700, Soren Brinkmann wrote: > > Add a driver for SILabs 570, 571, 598, 599 programmable oscillators. > > The devices generate low-jitter clock signals and are reprogrammable via > > an I2C interface. > > > > Cc: Guenter Roeck <linux@xxxxxxxxxxxx> > > Signed-off-by: Soren Brinkmann <soren.brinkmann@xxxxxxxxxx> > > --- > > v4: > > - actually check and handle error on clk_set_rate() call > > > > v3: > > - add delay in the path for small frequency changes, which can take up > > to 100us according to the data sheet > > - use real range for usleep_range() argument > > - use dev_err() over dev_warn() in set_rate() > > - add list of applicable devices for 7ppm DT prop > > - remove comments regarding platform data > > - ignore 7ppm DT prop for incompatible devices > > - replace raw numbers with #defines > > - convert DT prop 'temperature-stability' from boolean to u32 > > - make 'temperature-stability' DT prop required (actually not fully > > true, for 59x it is ignored and the driver does not require its > > presence) > > > > v2: > > - document clock-output-names in bindings documentation > > - don't use wildcards in compatibility string > > - change Kconfig entry to "... 570 and compatible devices" > > - change some indentation flaws > > - use 10000 as MIN and MAX value in usleep_range > > - fail probe() if 'factory-fout' is not provided in DT > > - default factory fout #defines removed > > - use i2c driver_data instead of OF data > > - remove some related structs and data > > - rename DT property 'initial-fout' => 'clock-frequency' (like si5351 > > driver) > > - add some more details regarding the 'factory-fout' DT property > > --- > > .../devicetree/bindings/clock/silabs,si570.txt | 39 ++ > > drivers/clk/Kconfig | 10 + > > drivers/clk/Makefile | 1 + > > drivers/clk/clk-si570.c | 536 +++++++++++++++++++++ > > 4 files changed, 586 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/clock/silabs,si570.txt > > create mode 100644 drivers/clk/clk-si570.c > > > > diff --git a/Documentation/devicetree/bindings/clock/silabs,si570.txt b/Documentation/devicetree/bindings/clock/silabs,si570.txt > > new file mode 100644 > > index 0000000..26aab5c > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/clock/silabs,si570.txt > > @@ -0,0 +1,39 @@ > > +Binding for Silicon Labs 570, 571, 598 and 599 programmable > > +I2C clock generators. > > + > > +Reference > > +This binding uses the common clock binding[1]. Details about the devices can be > > +found in the data sheets[2][3]. > > + > > +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt > > +[2] Si570/571 Data Sheet > > + http://www.silabs.com/Support%20Documents/TechnicalDocs/si570.pdf > > +[3] Si598/599 Data Sheet > > + http://www.silabs.com/Support%20Documents/TechnicalDocs/si598-99.pdf > > + > > +Required properties: > > + - compatible: Shall be one of "silabs,si570", "silabs,si571", > > + "silabs,si598", "silabs,si599" > > + - reg: I2C device address. > > + - #clock-cells: From common clock bindings: Shall be 0. > > + - factory-fout: Factory set default frequency. This frequency is part specific. > > + The correct frequency for the part used has to be provided in > > + order to generate the correct output frequencies. For more > > + details, please refer to the data sheet. > > + - temperature-stability: Temperature stability of the device. Should be one of: > > + 7, 20, 50 or 100. > > + > It might make sense to specify that this is in microseconds. ppm, but yes giving the unit is a good idea. > > > +Optional properties: > > + - clock-output-names: From common clock bindings. Recommended to be "si570". > > + - clock-frequency: Output frequency to generate. This defines the output > > + frequency set during boot. It can be reprogrammed during > > + runtime through the common clock framework. > > + > > +Example: > > + si570: clock-generator@5d { > > + #clock-cells = <0>; > > + compatible = "silabs,si570"; > > + temperatur-stability = <50>; > > temperature damn typos. > > > + reg = <0x5d>; > > + factory-fout = <156250000>; > > + }; [...] > > diff --git a/drivers/clk/clk-si570.c b/drivers/clk/clk-si570.c > > new file mode 100644 > > index 0000000..13c2091 > > --- /dev/null > > +++ b/drivers/clk/clk-si570.c [...] > > +static int si570_probe(struct i2c_client *client, > > + const struct i2c_device_id *id) > > +{ > > + struct clk_si570 *data; > > + struct clk_init_data init; > > + struct clk *clk; > > + u32 initial_fout, factory_fout, stability; > > + int err; > > + enum clk_si570_variant variant = id->driver_data; > > + > > + data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL); > > + if (!data) > > + return -ENOMEM; > > + > > + init.ops = &si570_clk_ops; > > + init.flags = CLK_IS_ROOT; > > + init.num_parents = 0; > > + data->hw.init = &init; > > + data->i2c_client = client; > > + > > + if (variant == si57x) { > > + err = of_property_read_u32(client->dev.of_node, > > + "temperature-stability", &stability); > > + if (err) { > > + dev_err(&client->dev, > > + "'temperature-stability' property missing\n"); > > + return err; > > + } > > + /* adjust register offsets for 7ppm devices */ > > + if (stability == 7) > > + data->div_offset = SI570_DIV_OFFSET_7PPM; > > + > > + data->max_freq = SI570_MAX_FREQ; > > + } else { > > + data->max_freq = SI598_MAX_FREQ; > > + } > > + > > + if (of_property_read_string(client->dev.of_node, "clock-output-names", > > + &init.name)) > > + init.name = client->dev.of_node->name; > > + > > + err = of_property_read_u32(client->dev.of_node, "factory-fout", > > + &factory_fout); > > + if (err) { > > + dev_err(&client->dev, "'factory-fout' property missing\n"); > > + return err; > > + } > > + > > + data->regmap = devm_regmap_init_i2c(client, &si570_regmap_config); > > + if (IS_ERR(data->regmap)) { > > + dev_err(&client->dev, "failed to allocate register map\n"); > > + return PTR_ERR(data->regmap); > > + } > > + > > + i2c_set_clientdata(client, data); > > + err = si570_get_defaults(data, factory_fout); > > + if (err) > > + return err; > > + > > + clk = devm_clk_register(&client->dev, &data->hw); > > + if (IS_ERR(clk)) { > > + dev_err(&client->dev, "clock registration failed\n"); > > + return PTR_ERR(clk); > > + } > > + err = of_clk_add_provider(client->dev.of_node, of_clk_src_simple_get, > > + clk); > > + if (err) { > > + dev_err(&client->dev, "unable to add clk provider\n"); > > + return err; > > + } > > + > > + /* Read the requested initial output frequency from device tree */ > > + if (!of_property_read_u32(client->dev.of_node, "clock-frequency", > > + &initial_fout)) { > > + err = clk_set_rate(clk, initial_fout); > > + if (err) { > > + of_clk_del_provider(client->dev.of_node); > > + clk_unregister(data->hw.clk); > > Is that needed ? I would have thought it isn't because you use a devm_ function > to register it. > > Not that I understand the clk code, but getting clk from the registration > function and unregistering hw.clk (without seting it) sems a bit odd. > Is it well defined that you have to unregister hw.clk ? I have to double check. I thought the managed interface is only saving you a call to clk_put() but I may be wrong. Sören -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
