This patch makes two additions to GPIO support:
First, it adds function gpio_read_in_bit() to read the a bit from the GPIO Input Register (GPIOx_IR) in the same way that function gpio_read_out_bit() reads a bit from the GPIO Output Register (GPIOx_OR).
Second, it modifies function gpio_set_chip_configuration() to provide an additional option for configuring the GPIO from the "CFG_4xx_GPIO_TABLE".
According to the 440EPx User's Manual, when an alternate output is used, the three-state control is configured in one of two ways, depending on the particular output. The first option is to select the corresponding alternate three-state control in the GPIOx_TRSH/L registers. The second option is to select the GPIO Three-State Control Register (GPIOx_TCR) in the GPIOx_TRSH/L registers, and set the corresponding bit in the GPIOx_TCR register to enable the output. For example, the Manual specifies configuring the GPIO00 Alternate 1 Signal (PreAddr07) to use the alternate three-state control (first option), and specifies configuring the GPIO32 Alternate 1 Signal (USB2OM0) with the output enabled in the GPIOx_TCR register (second option).
Currently, gpio_set_chip_configuration() configures all alternate signal outputs to use the first option. This patch allow the second option to be selected by setting the "out_val" element in the table entry to "GPIO_OUT_1". The first option is used when the "out_val" element is set to "GPIO_OUT_0". Because "out_val" is not currently used when an alternate signal is selected, and because all current GPIO tables set "out_val" to "GPIO_OUT_0" for all alternate signals, this patch should not change any existing configurations.
Signed-off-by: Larry Johnson lrj@acm.org --- cpu/ppc4xx/gpio.c | 63 ++++++++++++++++++++++++++++++----------------- include/asm-ppc/gpio.h | 1 + 2 files changed, 41 insertions(+), 23 deletions(-)
diff --git a/cpu/ppc4xx/gpio.c b/cpu/ppc4xx/gpio.c index 7b09a2f..37d3fa8 100644 --- a/cpu/ppc4xx/gpio.c +++ b/cpu/ppc4xx/gpio.c @@ -27,7 +27,7 @@ #include <asm/gpio.h>
#if defined(CFG_4xx_GPIO_TABLE) -gpio_param_s gpio_tab[GPIO_GROUP_MAX][GPIO_MAX] = CFG_4xx_GPIO_TABLE; +gpio_param_s const gpio_tab[GPIO_GROUP_MAX][GPIO_MAX] = CFG_4xx_GPIO_TABLE; #endif
#if defined(GPIO0_OSRL) @@ -120,6 +120,18 @@ int gpio_read_out_bit(int pin) return (in_be32((void *)GPIO0_OR + offs) & GPIO_VAL(pin) ? 1 : 0); }
+int gpio_read_in_bit(int pin) +{ + u32 offs = 0; + + if (pin >= GPIO_MAX) { + offs = 0x100; + pin -= GPIO_MAX; + } + + return (in_be32((void *)GPIO0_IR + offs) & GPIO_VAL(pin) ? 1 : 0); +} + #if defined(CFG_4xx_GPIO_TABLE) void gpio_set_chip_configuration(void) { @@ -171,6 +183,8 @@ void gpio_set_chip_configuration(void) if ((gpio_tab[gpio_core][i].in_out == GPIO_OUT) || (gpio_tab[gpio_core][i].in_out == GPIO_BI)) {
+ u32 gpio_alt_sel = 0; + switch (gpio_tab[gpio_core][i].alt_nb) { case GPIO_SEL: /* @@ -199,37 +213,40 @@ void gpio_set_chip_configuration(void) break;
case GPIO_ALT1: - reg = in_be32((void *)GPIO_OS(core_add+offs)) - & ~(GPIO_MASK >> (j*2)); - reg = reg | (GPIO_ALT1_SEL >> (j*2)); - out_be32((void *)GPIO_OS(core_add+offs), reg); - reg = in_be32((void *)GPIO_TS(core_add+offs)) - & ~(GPIO_MASK >> (j*2)); - reg = reg | (GPIO_ALT1_SEL >> (j*2)); - out_be32((void *)GPIO_TS(core_add+offs), reg); + gpio_alt_sel = GPIO_ALT1_SEL; break;
case GPIO_ALT2: - reg = in_be32((void *)GPIO_OS(core_add+offs)) - & ~(GPIO_MASK >> (j*2)); - reg = reg | (GPIO_ALT2_SEL >> (j*2)); - out_be32((void *)GPIO_OS(core_add+offs), reg); - reg = in_be32((void *)GPIO_TS(core_add+offs)) - & ~(GPIO_MASK >> (j*2)); - reg = reg | (GPIO_ALT2_SEL >> (j*2)); - out_be32((void *)GPIO_TS(core_add+offs), reg); + gpio_alt_sel = GPIO_ALT2_SEL; break;
case GPIO_ALT3: + gpio_alt_sel = GPIO_ALT3_SEL; + break; + } + + if (0 != gpio_alt_sel) { reg = in_be32((void *)GPIO_OS(core_add+offs)) & ~(GPIO_MASK >> (j*2)); - reg = reg | (GPIO_ALT3_SEL >> (j*2)); + reg = reg | (gpio_alt_sel >> (j*2)); out_be32((void *)GPIO_OS(core_add+offs), reg); - reg = in_be32((void *)GPIO_TS(core_add+offs)) - & ~(GPIO_MASK >> (j*2)); - reg = reg | (GPIO_ALT3_SEL >> (j*2)); - out_be32((void *)GPIO_TS(core_add+offs), reg); - break; + + if (gpio_tab[gpio_core][i].out_val == GPIO_OUT_1) { + reg = in_be32((void *)GPIO_TCR(core_add)) + | (0x80000000 >> (i)); + out_be32((void *)GPIO_TCR(core_add), reg); + reg = in_be32((void *)GPIO_TS(core_add+offs)) + & ~(GPIO_MASK >> (j*2)); + out_be32((void *)GPIO_TS(core_add+offs), reg); + } else { + reg = in_be32((void *)GPIO_TCR(core_add)) + & ~(0x80000000 >> (i)); + out_be32((void *)GPIO_TCR(core_add), reg); + reg = in_be32((void *)GPIO_TS(core_add+offs)) + & ~(GPIO_MASK >> (j*2)); + reg = reg | (gpio_alt_sel >> (j*2)); + out_be32((void *)GPIO_TS(core_add+offs), reg); + } } } } diff --git a/include/asm-ppc/gpio.h b/include/asm-ppc/gpio.h index d0c3eba..c3a4a88 100644 --- a/include/asm-ppc/gpio.h +++ b/include/asm-ppc/gpio.h @@ -88,6 +88,7 @@ typedef struct { void gpio_config(int pin, int in_out, int gpio_alt, int out_val); void gpio_write_bit(int pin, int val); int gpio_read_out_bit(int pin); +int gpio_read_in_bit(int pin); void gpio_set_chip_configuration(void);
#endif /* __ASM_PPC_GPIO_H */