> -----Original Message----- > From: Guenter Roeck [mailto:groeck7@xxxxxxxxx] On Behalf Of Guenter Roeck > Sent: Tuesday, January 10, 2023 2:52 AM > To: gene_chen(陳俊宇) <gene_chen@xxxxxxxxxxx>; robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx; heikki.krogerus@xxxxxxxxxxxxxxx > Cc: gregkh@xxxxxxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx > Subject: Re: [PATCH 2/2] usb: typec: tcpci_rt1718s: Add Richtek RT1718S tcpci driver > > On 1/9/23 01:31, gene_chen@xxxxxxxxxxx wrote: > > From: Gene Chen <gene_chen@xxxxxxxxxxx> > > > > Richtek RT1718S is highly integrated TCPC and Power Delivery (PD) > > controller with IEC-ESD Protection on SBU/CC/DP/DM, USB2.0 Switch, > > Charging Port Controller and Power-Path Control. > > > > Signed-off-by: Gene Chen <gene_chen@xxxxxxxxxxx> > > --- > > drivers/usb/typec/tcpm/Kconfig | 9 + > > drivers/usb/typec/tcpm/Makefile | 1 + > > drivers/usb/typec/tcpm/tcpci_rt1718s.c | 349 +++++++++++++++++++++++++++++++++ > > 3 files changed, 359 insertions(+) > > create mode 100644 drivers/usb/typec/tcpm/tcpci_rt1718s.c > > > > diff --git a/drivers/usb/typec/tcpm/Kconfig > > b/drivers/usb/typec/tcpm/Kconfig index e6b88ca..f0efb34 100644 > > --- a/drivers/usb/typec/tcpm/Kconfig > > +++ b/drivers/usb/typec/tcpm/Kconfig > > @@ -27,6 +27,15 @@ config TYPEC_RT1711H > > Type-C Port Controller Manager to provide USB PD and USB > > Type-C functionalities. > > > > +config TYPEC_RT1718S > > +tristate "Richtek RT1718S Type-C chip driver" > > +depends on I2C > > +help > > + Richtek RT1718S Type-C chip driver that works with > > + Type-C Port Controller Manager to provide USB PD and USB > > + Type-C functionalities. > > + Additionally, it supports BC1.2 and power-path control. > > + > > config TYPEC_MT6360 > > tristate "Mediatek MT6360 Type-C driver" > > depends on MFD_MT6360 > > diff --git a/drivers/usb/typec/tcpm/Makefile > > b/drivers/usb/typec/tcpm/Makefile index 906d9dc..db33ffc 100644 > > --- a/drivers/usb/typec/tcpm/Makefile > > +++ b/drivers/usb/typec/tcpm/Makefile > > @@ -5,6 +5,7 @@ obj-$(CONFIG_TYPEC_WCOVE)+= typec_wcove.o > > typec_wcove-y:= wcove.o > > obj-$(CONFIG_TYPEC_TCPCI)+= tcpci.o > > obj-$(CONFIG_TYPEC_RT1711H)+= tcpci_rt1711h.o > > +obj-$(CONFIG_TYPEC_RT1718S)+= tcpci_rt1718s.o > > obj-$(CONFIG_TYPEC_MT6360)+= tcpci_mt6360.o > > obj-$(CONFIG_TYPEC_TCPCI_MT6370)+= tcpci_mt6370.o > > obj-$(CONFIG_TYPEC_TCPCI_MAXIM)+= tcpci_maxim.o > > diff --git a/drivers/usb/typec/tcpm/tcpci_rt1718s.c > > b/drivers/usb/typec/tcpm/tcpci_rt1718s.c > > new file mode 100644 > > index 00000000..305b39c > > --- /dev/null > > +++ b/drivers/usb/typec/tcpm/tcpci_rt1718s.c > > + > > +if (*(u8 *)reg == RT1718S_P1PREFIX) { > > +xfer[0].len = 1, > > +xfer[0].buf = (u8 *)(reg + 1); > > Pointer arithmetic on void * (see below). > yes, should be xfer[0].buf = (u8 *)reg + 1; > > +} > > There is a lot of context here which needs explanation. The code extracts the upper 8 bit of the register address and drops it if the value is 0. > So the address is either 8 bit or 16 bit depending on the register address. > Also, this only works because reg_format_endian is set to big endian. > > This really needs to be documented. > > Assigning the values to len and buf twice is really bad style. > Please use if/else. > Because of rt1718s address which is more than 1 page(0x00-0xFF), hw design i2c pattern with register has 2 byte to access another page(0xF200-0xF2FF). The upper byte is set to 0xF2 indicated page 2. > > + > > +if (*(u8 *)val == RT1718S_P1PREFIX) { > > +xfer.len = val_size - 1; > > +xfer.buf = (u8 *)(val + 1); > > +} > > + > > Same comments as above. Also, typecast seems wrong. Shouldn't it be > ((u8 *)val) + 1) ? My memory may defeat me, but I think that pointer arithmetic on void * is undefined or even illegal. > > You are right, I will fix it, thanks. > > +if (ret < 0) > > +return ret; > > +if (ret != 1) > > +return -EIO; > > + > > +return 0; > > +} > > + > > +static const struct regmap_bus rt1718s_regmap_bus = { > > +.read= rt1718s_regmap_read, > > +.write= rt1718s_regmap_write, > > +}; > > + > > This needs documentation: Why not use standard regmap functions ? > Yes, I know, it is because of the ubusual addressing format used by the chip, but it still needs to be explained. Not everyone should have to read the datasheet to understand the code. > Should I add comment before declare rt1718s_regmap_bus? /* * Because of rt1718s address which is more than 1 page(0x00-0xFF), * hw design i2c pattern with register has 2 byte to access another page(0xF200-0xF2FF). * The upper byte is set to 0xF2 indicated page 2. */ > > +static int rt1718s_sw_reset(struct rt1718s_chip *chip) { > > +int ret; > > + > > +ret = regmap_update_bits(chip->tdata.regmap, RT1718S_SYS_CTRL3, > > + RT1718S_SWRESET_MASK, RT1718S_SWRESET_MASK); > > +if (ret < 0) > > +return ret; > > + > > +/* Wait for IC to reset done*/ > > +usleep_range(1000, 2000); > > + > > "RT1718S will not response to the I2C commands for 2ms after writing SOFT_RESET" > > Timeout needs to be at least 2 ms. > ACK > > +return 0; > > +} > > + > > +static int rt1718s_check_chip_exist(struct i2c_client *i2c) { > > +int ret; > > + > > +ret = i2c_smbus_read_word_data(i2c, TCPC_VENDOR_ID); > > +if (ret < 0) > > +return ret; > > +if (ret != RT1718S_VID) { > > +dev_err(&i2c->dev, "vid is not correct, 0x%04x\n", ret); > > +return -ENODEV; > > +} > > +ret = i2c_smbus_read_word_data(i2c, TCPC_PRODUCT_ID); > > +if (ret < 0) > > +return ret; > > +if (ret != RT1718S_PID) { > > +dev_err(&i2c->dev, "pid is not correct, 0x%04x\n", ret); > > +return -ENODEV; > > +} > > +return 0; > > +} > > + > > +static int rt1718s_probe(struct i2c_client *i2c) { > > +struct rt1718s_chip *chip; > > +struct gpio_desc *gpiod; > > +int ret; > > +u16 clr_events = 0; > > + > > +ret = rt1718s_check_chip_exist(i2c); > > +if (ret < 0) { > > +dev_err(&i2c->dev, "check vid/pid fail(%d)\n", ret); > > Double error message. > ACK, I will remove it. > > +return ret; > > +} > > + > > +chip = devm_kzalloc(&i2c->dev, sizeof(*chip), GFP_KERNEL); > > +if (!chip) > > +return -ENOMEM; > > + > > +chip->dev = &i2c->dev; > > + > > +chip->tdata.regmap = devm_regmap_init(&i2c->dev, > > + &rt1718s_regmap_bus, &i2c->dev, > > + &rt1718s_regmap_config); > > +if (IS_ERR(chip->tdata.regmap)) > > +return dev_err_probe(&i2c->dev, PTR_ERR(chip->tdata.regmap), > > + "Failed to init regmap\n"); > > + > > +chip->vbus = devm_regulator_get(&i2c->dev, "vbus"); > > +if (IS_ERR(chip->vbus)) > > +return dev_err_probe(&i2c->dev, PTR_ERR(chip->vbus), > > + "Failed to get vbus regulator\n"); > > + > > +ret = rt1718s_sw_reset(chip); > > +if (ret < 0) > > +return ret; > > + > > +ret = regmap_raw_write(chip->tdata.regmap, TCPC_ALERT_MASK, &clr_events, > > + sizeof(clr_events)); > > + > > +chip->tdata.init = rt1718s_init; > > +chip->tdata.set_vbus = rt1718s_set_vbus; > > +chip->tcpci = tcpci_register_port(&i2c->dev, &chip->tdata); > > +if (IS_ERR(chip->tcpci)) > > +return dev_err_probe(&i2c->dev, PTR_ERR(chip->tcpci), > > + "Failed to register tcpci port\n"); > > + > > +/* for platform set gpio default inpull_high */ > > +gpiod = devm_gpiod_get(&i2c->dev, NULL, GPIOD_IN); > > +if (IS_ERR(gpiod)) > > +return dev_err_probe(&i2c->dev, PTR_ERR(gpiod), > > + "Failed to get gpio\n"); > > + > > +ret = devm_request_threaded_irq(&i2c->dev, i2c->irq, NULL, > > +rt1718s_irq, IRQF_ONESHOT, > > +dev_name(&i2c->dev), chip); > > +if (ret) { > > +dev_err(chip->dev, "Failed to register irq\n"); > > +tcpci_unregister_port(chip->tcpci); > > +return ret; > > +} > > + > > +device_init_wakeup(&i2c->dev, true); > > +i2c_set_clientdata(i2c, chip); > > + > > +dev_info(&i2c->dev, "%s:successfully\n", __func__); > > Nore logging noise. > ACK > > +return 0; > > +} > > + > > +static void rt1718s_remove(struct i2c_client *i2c) { > > +struct rt1718s_chip *chip = i2c_get_clientdata(i2c); > > + > > +tcpci_unregister_port(chip->tcpci); > > +} > > + > > +static int __maybe_unused rt1718s_suspend(struct device *dev) { > > +struct i2c_client *i2c = to_i2c_client(dev); > > + > > +if (device_may_wakeup(dev)) > > +enable_irq_wake(i2c->irq); > > +disable_irq(i2c->irq); > > + > > +return 0; > > +} > > + > > +static int __maybe_unused rt1718s_resume(struct device *dev) { > > +struct i2c_client *i2c = to_i2c_client(dev); > > + > > +if (device_may_wakeup(dev)) > > +disable_irq_wake(i2c->irq); > > +enable_irq(i2c->irq); > > + > > +return 0; > > +} > > + > > +static SIMPLE_DEV_PM_OPS(rt1718s_pm_ops, rt1718s_suspend, > > +rt1718s_resume); > > + > > +static const struct of_device_id __maybe_unused rt1718s_of_id[] = { > > +{ .compatible = "richtek,rt1718s", }, > > +{}, > > +}; > > +MODULE_DEVICE_TABLE(of, rt1718s_of_id); > > + > > +static struct i2c_driver rt1718s_i2c_driver = { > > +.driver = { > > +.name = "rt1718s", > > +.pm = &rt1718s_pm_ops, > > +.of_match_table = rt1718s_of_id, > > +}, > > +.probe_new = rt1718s_probe, > > +.remove = rt1718s_remove, > > +}; > > +module_i2c_driver(rt1718s_i2c_driver); > > + > > +MODULE_AUTHOR("Gene Chen <gene_chen@xxxxxxxxxxx>"); > > +MODULE_DESCRIPTION("RT1718S USB Type-C Port Controller Interface > > +Driver"); MODULE_LICENSE("GPL");
