On 4/9/21 3:40 PM, Aswath Govindraju wrote: > The driver adds support for generic CAN transceivers. Currently > the modes supported by this driver are standby and normal modes for TI > TCAN1042 and TCAN1043 CAN transceivers. > > The transceiver is modelled as a phy with pins controlled by gpios, to put > the transceiver in various device functional modes. It also gets the phy > attribute max_link_rate for the usage of m_can drivers. This driver should be independent of CAN driver, so you should not mention a specific driver here. > Signed-off-by: Aswath Govindraju <a-govindraju@xxxxxx> > --- > drivers/phy/Kconfig | 9 ++ > drivers/phy/Makefile | 1 + > drivers/phy/phy-can-transceiver.c | 140 ++++++++++++++++++++++++++++++ > 3 files changed, 150 insertions(+) > create mode 100644 drivers/phy/phy-can-transceiver.c > > diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig > index 54c1f2f0985f..51902b629fc6 100644 > --- a/drivers/phy/Kconfig > +++ b/drivers/phy/Kconfig > @@ -61,6 +61,15 @@ config USB_LGM_PHY > interface to interact with USB GEN-II and USB 3.x PHY that is part > of the Intel network SOC. > > +config PHY_CAN_TRANSCEIVER > + tristate "CAN transceiver PHY" > + select GENERIC_PHY > + help > + This option enables support for CAN transceivers as a PHY. This > + driver provides function for putting the transceivers in various > + functional modes using gpios and sets the attribute max link > + rate, for mcan drivers. > + > source "drivers/phy/allwinner/Kconfig" > source "drivers/phy/amlogic/Kconfig" > source "drivers/phy/broadcom/Kconfig" > diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile > index adac1b1a39d1..9c66101c9605 100644 > --- a/drivers/phy/Makefile > +++ b/drivers/phy/Makefile > @@ -9,6 +9,7 @@ obj-$(CONFIG_PHY_LPC18XX_USB_OTG) += phy-lpc18xx-usb-otg.o > obj-$(CONFIG_PHY_XGENE) += phy-xgene.o > obj-$(CONFIG_PHY_PISTACHIO_USB) += phy-pistachio-usb.o > obj-$(CONFIG_USB_LGM_PHY) += phy-lgm-usb.o > +obj-$(CONFIG_PHY_CAN_TRANSCEIVER) += phy-can-transceiver.o > obj-y += allwinner/ \ > amlogic/ \ > broadcom/ \ > diff --git a/drivers/phy/phy-can-transceiver.c b/drivers/phy/phy-can-transceiver.c > new file mode 100644 > index 000000000000..14496f6e1666 > --- /dev/null > +++ b/drivers/phy/phy-can-transceiver.c > @@ -0,0 +1,140 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * phy-can-transceiver.c - phy driver for CAN transceivers > + * > + * Copyright (C) 2021 Texas Instruments Incorporated - http://www.ti.com > + * > + */ > +#include<linux/phy/phy.h> > +#include<linux/platform_device.h> > +#include<linux/module.h> > +#include<linux/gpio.h> > +#include<linux/gpio/consumer.h> > + > +struct can_transceiver_data { > + u32 flags; > +#define STB_PRESENT BIT(0) > +#define EN_PRESENT BIT(1) please add a common prefix to the defines > +}; > + > +struct can_transceiver_phy { > + struct phy *generic_phy; > + struct gpio_desc *standby_gpio; > + struct gpio_desc *enable_gpio; > +}; > + > +/* Power on function */ > +static int can_transceiver_phy_power_on(struct phy *phy) > +{ > + struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy); > + > + if (can_transceiver_phy->standby_gpio) > + gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 0); > + if (can_transceiver_phy->enable_gpio) > + gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 1); Please add a newline before the return. > + return 0; > +} > + > +/* Power off function */ > +static int can_transceiver_phy_power_off(struct phy *phy) > +{ > + struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy); > + > + if (can_transceiver_phy->standby_gpio) > + gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 1); > + if (can_transceiver_phy->enable_gpio) > + gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 0); same here > + return 0; > +} > + > +static const struct phy_ops can_transceiver_phy_ops = { > + .power_on = can_transceiver_phy_power_on, > + .power_off = can_transceiver_phy_power_off, > + .owner = THIS_MODULE, > +}; > + > +static const struct can_transceiver_data tcan1042_drvdata = { > + .flags = STB_PRESENT, > +}; > + > +static const struct can_transceiver_data tcan1043_drvdata = { > + .flags = STB_PRESENT | EN_PRESENT, > +}; > + > +static const struct of_device_id can_transceiver_phy_ids[] = { > + { > + .compatible = "ti,tcan1042", > + .data = &tcan1042_drvdata > + }, > + { > + .compatible = "ti,tcan1043", > + .data = &tcan1043_drvdata > + }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, can_transceiver_phy_ids); > + > +int can_transceiver_phy_probe(struct platform_device *pdev) > +{ > + struct phy_provider *phy_provider; > + struct device *dev = &pdev->dev; > + struct can_transceiver_phy *can_transceiver_phy; > + const struct can_transceiver_data *drvdata; > + const struct of_device_id *match; > + struct phy *phy; > + struct gpio_desc *standby_gpio; > + struct gpio_desc *enable_gpio; > + u32 max_bitrate = 0; > + > + can_transceiver_phy = devm_kzalloc(dev, sizeof(struct can_transceiver_phy), GFP_KERNEL); error handling? > + > + match = of_match_node(can_transceiver_phy_ids, pdev->dev.of_node); > + drvdata = match->data; > + > + phy = devm_phy_create(dev, dev->of_node, > + &can_transceiver_phy_ops); > + if (IS_ERR(phy)) { > + dev_err(dev, "failed to create can transceiver phy\n"); > + return PTR_ERR(phy); > + } > + > + device_property_read_u32(dev, "max-bitrate", &max_bitrate); > + phy->attrs.max_link_rate = max_bitrate / 1000000; The problem is, there are CAN transceivers with a max of 83.3 kbit/s or 125 kbit/s. > + can_transceiver_phy->generic_phy = phy; > + > + if (drvdata->flags & STB_PRESENT) { > + standby_gpio = devm_gpiod_get(dev, "standby", GPIOD_OUT_LOW); please use only one space after the ",". Why do you request the gpio standby low? > + if (IS_ERR(standby_gpio)) > + return PTR_ERR(standby_gpio); > + can_transceiver_phy->standby_gpio = standby_gpio; > + } > + > + if (drvdata->flags & EN_PRESENT) { > + enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW); > + if (IS_ERR(enable_gpio)) > + return PTR_ERR(enable_gpio); > + can_transceiver_phy->enable_gpio = enable_gpio; > + } > + > + phy_set_drvdata(can_transceiver_phy->generic_phy, can_transceiver_phy); > + > + phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); > + > + return PTR_ERR_OR_ZERO(phy_provider); > +} > + > +static struct platform_driver can_transceiver_phy_driver = { > + .probe = can_transceiver_phy_probe, > + .driver = { > + .name = "can-transceiver-phy", > + .of_match_table = can_transceiver_phy_ids, > + }, > +}; > + > +module_platform_driver(can_transceiver_phy_driver); > + > +MODULE_AUTHOR("Faiz Abbas <faiz_abbas@xxxxxx>"); > +MODULE_AUTHOR("Aswath Govindraju <a-govindraju@xxxxxx>"); > +MODULE_DESCRIPTION("CAN TRANSCEIVER PHY driver"); > +MODULE_LICENSE("GPL v2"); > marc -- Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
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