Hi, On Fri, Mar 23, 2018 at 1:20 PM, Karthikeyan Ramasubramanian <kramasub@xxxxxxxxxxxxxx> wrote: > This bus driver supports the GENI based i2c hardware controller in the > Qualcomm SOCs. The Qualcomm Generic Interface (GENI) is a programmable > module supporting a wide range of serial interfaces including I2C. The > driver supports FIFO mode and DMA mode of transfer and switches modes > dynamically depending on the size of the transfer. > > Signed-off-by: Karthikeyan Ramasubramanian <kramasub@xxxxxxxxxxxxxx> > Signed-off-by: Sagar Dharia <sdharia@xxxxxxxxxxxxxx> > Signed-off-by: Girish Mahadevan <girishm@xxxxxxxxxxxxxx> > --- > drivers/i2c/busses/Kconfig | 13 + > drivers/i2c/busses/Makefile | 1 + > drivers/i2c/busses/i2c-qcom-geni.c | 650 +++++++++++++++++++++++++++++++++++++ > 3 files changed, 664 insertions(+) [...] > +/* > + * Hardware uses the underlying formula to calculate time periods of > + * SCL clock cycle. Firmware uses some additional cycles excluded from the > + * below formula and it is confirmed that the time periods are within > + * specification limits. I was hoping for more than just "oh, and there's a fudge factor", but I guess this is the best I'm going to get? > +static int geni_i2c_probe(struct platform_device *pdev) > +{ > + struct geni_i2c_dev *gi2c; > + struct resource *res; > + u32 proto, tx_depth; > + int ret; > + > + gi2c = devm_kzalloc(&pdev->dev, sizeof(*gi2c), GFP_KERNEL); > + if (!gi2c) > + return -ENOMEM; > + > + gi2c->se.dev = &pdev->dev; > + gi2c->se.wrapper = dev_get_drvdata(pdev->dev.parent); > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + gi2c->se.base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(gi2c->se.base)) > + return PTR_ERR(gi2c->se.base); > + > + gi2c->se.clk = devm_clk_get(&pdev->dev, "se"); > + if (IS_ERR(gi2c->se.clk)) { > + ret = PTR_ERR(gi2c->se.clk); > + dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret); > + return ret; > + } > + > + ret = device_property_read_u32(&pdev->dev, "clock-frequency", > + &gi2c->clk_freq_out); > + if (ret) { > + /* Clock frequency not specified, so default to 100kHz. */ > + dev_info(&pdev->dev, > + "Bus frequency not specified, default to 100kHz.\n"); If you happen to spin again, can you remove the comment since it's obvious from the string in the print? It looks a lot like this code: /* Print hello, world */ printf("hello, world\n"); In any case, that's a pretty minor nit, so I'll add: Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx> ...assuming that the bindings and "geni" code get Acked / landed somewhere. Ideally let's not land this before the geni code lands since if the geni API changes for some reason it'll cause us grief. -Doug -- 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