diff options
Diffstat (limited to 'drivers/gpio/gpio-exar.c')
| -rw-r--r-- | drivers/gpio/gpio-exar.c | 40 |
1 files changed, 35 insertions, 5 deletions
diff --git a/drivers/gpio/gpio-exar.c b/drivers/gpio/gpio-exar.c index d37de78247a6..482f678c893e 100644 --- a/drivers/gpio/gpio-exar.c +++ b/drivers/gpio/gpio-exar.c @@ -21,6 +21,12 @@ #define EXAR_OFFSET_MPIOLVL_HI 0x96 #define EXAR_OFFSET_MPIOSEL_HI 0x99 +/* + * The Device Configuration and UART Configuration Registers + * for each UART channel take 1KB of memory address space. + */ +#define EXAR_UART_CHANNEL_SIZE 0x400 + #define DRIVER_NAME "gpio_exar" static DEFINE_IDA(ida_index); @@ -31,26 +37,39 @@ struct exar_gpio_chip { int index; char name[20]; unsigned int first_pin; + /* + * The offset to the cascaded device's (if existing) + * Device Configuration Registers. + */ + unsigned int cascaded_offset; }; static unsigned int exar_offset_to_sel_addr(struct exar_gpio_chip *exar_gpio, unsigned int offset) { - return (offset + exar_gpio->first_pin) / 8 ? EXAR_OFFSET_MPIOSEL_HI - : EXAR_OFFSET_MPIOSEL_LO; + unsigned int pin = exar_gpio->first_pin + (offset % 16); + unsigned int cascaded = offset / 16; + unsigned int addr = pin / 8 ? EXAR_OFFSET_MPIOSEL_HI : EXAR_OFFSET_MPIOSEL_LO; + + return addr + (cascaded ? exar_gpio->cascaded_offset : 0); } static unsigned int exar_offset_to_lvl_addr(struct exar_gpio_chip *exar_gpio, unsigned int offset) { - return (offset + exar_gpio->first_pin) / 8 ? EXAR_OFFSET_MPIOLVL_HI - : EXAR_OFFSET_MPIOLVL_LO; + unsigned int pin = exar_gpio->first_pin + (offset % 16); + unsigned int cascaded = offset / 16; + unsigned int addr = pin / 8 ? EXAR_OFFSET_MPIOLVL_HI : EXAR_OFFSET_MPIOLVL_LO; + + return addr + (cascaded ? exar_gpio->cascaded_offset : 0); } static unsigned int exar_offset_to_bit(struct exar_gpio_chip *exar_gpio, unsigned int offset) { - return (offset + exar_gpio->first_pin) % 8; + unsigned int pin = exar_gpio->first_pin + (offset % 16); + + return pin % 8; } static int exar_get_direction(struct gpio_chip *chip, unsigned int offset) @@ -154,6 +173,17 @@ static int gpio_exar_probe(struct platform_device *pdev) return -ENOMEM; /* + * If cascaded, secondary xr17v354 or xr17v358 have the same amount + * of MPIOs as their primaries and the last 4 bits of the primary's + * PCI Device ID is the number of its UART channels. + */ + if (pcidev->device & GENMASK(15, 12)) { + ngpios += ngpios; + exar_gpio->cascaded_offset = (pcidev->device & GENMASK(3, 0)) * + EXAR_UART_CHANNEL_SIZE; + } + + /* * We don't need to check the return values of mmio regmap operations (unless * the regmap has a clock attached which is not the case here). */ |