From fdb7e884ad617f8aa69abdd7f39e3fdac85e081e Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Sat, 1 Jun 2019 00:37:56 +0200 Subject: i2c: iop: Use GPIO descriptors The IOP3xx has some elaborate code to directly slam the GPIO lines multiplexed with I2C down low before enablement, apparently a workaround for a hardware bug found in the early chips. After consulting the developer documentation for IOP80321 and IOP80331 I can clearly see that this may be useful for IOP80321 family (mach-iop32x) but it is highly dubious for any 80331 series or later chip: in these chips the lines are not multiplexed for UARTs. We convert the code to pass optional GPIO descriptors and register these only on the 80321-based boards where it makes sense, optionally obtain them in the driver and use the gpiod_set_raw_value() to ascertain the line gets driven low when needed. The GPIO driver does not give the GPIO chip a reasonable label so the patch also adds that so that these machine descriptor tables can be used. Signed-off-by: Linus Walleij Acked-by: Arnd Bergmann Acked-by: Dan Williams Signed-off-by: Wolfram Sang --- arch/arm/mach-iop32x/n2100.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arm/mach-iop32x/n2100.c') diff --git a/arch/arm/mach-iop32x/n2100.c b/arch/arm/mach-iop32x/n2100.c index 23e8c93515d4..c780b6e82ad9 100644 --- a/arch/arm/mach-iop32x/n2100.c +++ b/arch/arm/mach-iop32x/n2100.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include #include @@ -345,6 +346,7 @@ device_initcall(n2100_request_gpios); static void __init n2100_init_machine(void) { register_iop32x_gpio(); + gpiod_add_lookup_table(&iop3xx_i2c0_gpio_lookup); platform_device_register(&iop3xx_i2c0_device); platform_device_register(&n2100_flash_device); platform_device_register(&n2100_serial_device); -- cgit