diff options
Diffstat (limited to 'drivers/serial/serial_bcm283x_pl011.c')
-rw-r--r-- | drivers/serial/serial_bcm283x_pl011.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/drivers/serial/serial_bcm283x_pl011.c b/drivers/serial/serial_bcm283x_pl011.c new file mode 100644 index 0000000000..bfd39f84f3 --- /dev/null +++ b/drivers/serial/serial_bcm283x_pl011.c @@ -0,0 +1,73 @@ +/* + * Copyright (c) 2018 Alexander Graf <agraf@suse.de> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <dm.h> +#include <asm/gpio.h> +#include <dm/pinctrl.h> +#include <dm/platform_data/serial_pl01x.h> +#include "serial_pl01x_internal.h" + +/* + * Check if this serial device is muxed + * + * The serial device will only work properly if it has been muxed to the serial + * pins by firmware. Check whether that happened here. + * + * @return true if serial device is muxed, false if not + */ +static bool bcm283x_is_serial_muxed(void) +{ + int serial_gpio = 15; + struct udevice *dev; + + if (uclass_first_device(UCLASS_PINCTRL, &dev) || !dev) + return false; + + if (pinctrl_get_gpio_mux(dev, 0, serial_gpio) != BCM2835_GPIO_ALT0) + return false; + + return true; +} + +static int bcm283x_pl011_serial_ofdata_to_platdata(struct udevice *dev) +{ + struct pl01x_serial_platdata *plat = dev_get_platdata(dev); + int ret; + + /* Don't spawn the device if it's not muxed */ + if (!bcm283x_is_serial_muxed()) + return -ENODEV; + + ret = pl01x_serial_ofdata_to_platdata(dev); + if (ret) + return ret; + + /* + * TODO: Reinitialization doesn't always work for now, just skip + * init always - we know we're already initialized + */ + plat->skip_init = true; + + return 0; +} + +static const struct udevice_id bcm283x_pl011_serial_id[] = { + {.compatible = "brcm,bcm2835-pl011", .data = TYPE_PL011}, + {} +}; + +U_BOOT_DRIVER(bcm283x_pl011_uart) = { + .name = "bcm283x_pl011", + .id = UCLASS_SERIAL, + .of_match = of_match_ptr(bcm283x_pl011_serial_id), + .ofdata_to_platdata = of_match_ptr(bcm283x_pl011_serial_ofdata_to_platdata), + .platdata_auto_alloc_size = sizeof(struct pl01x_serial_platdata), + .probe = pl01x_serial_probe, + .ops = &pl01x_serial_ops, + .flags = DM_FLAG_PRE_RELOC, + .priv_auto_alloc_size = sizeof(struct pl01x_priv), +}; |