ppc4xx: Add functionality to GPIO support

PATCH New Lawrence R. Johnson 2 participants 3 messages Jan 3, 2008

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Lawrence R. Johnson

author

2008-01-03 16:53 UTC #0 lore raw

PATCH 1/1 ppc4xx: Add functionality to GPIO support

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 <[email protected]>

---
 cpu/ppc4xx/gpio.c      |   65 ++++++++++++++++++++++++++++++-----------------
 include/asm-ppc/gpio.h |    3 +-
 2 files changed, 43 insertions(+), 25 deletions(-)

cpu/ppc4xx/gpio.c +41 ~~-24~~

index 7b09a2f..5db0673 100644
@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2007
+ * (C) Copyright 2007-2008
  * Stefan Roese, DENX Software Engineering, sr at denx.de.
  *
  * See file CREDITS for list of people who contributed to this

@@ -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);
+					}
 				}
 			}
 		}

include/asm-ppc/gpio.h +2 -1

index d0c3eba..ccc7bd2 100644
@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2007
+ * (C) Copyright 2007-2008
  * Stefan Roese, DENX Software Engineering, sr at denx.de.
  *
  * See file CREDITS for list of people who contributed to this

@@ -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 */

Wolfgang Denk

2008-01-03 19:26 UTC #1 lore raw

PATCH 1/1 ppc4xx: Add functionality to GPIO support

Quoted 2 lines · In message <[email protected]> you wrote:

Signed-off-by Larry Johnson <[email protected]>

...

Quoted 2 lines

- * (C) Copyright 2007
+ * (C) Copyright 2007-2008

If you make a change, how can this change Stefan's Copyright?

Please do not mess with other people's copyrights!

Best regards,

Wolfgang Denk

Signature · 5 lines

DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Q:  How many IBM CPU's does it take to execute a job?
A:  Four; three to hold it down, and one to rip its head off.

Lawrence R. Johnson

author

2008-01-03 23:36 UTC #2 lore raw

PATCH 1/1 ppc4xx: Add functionality to GPIO support

Quoted 6 lines · Wolfgang Denk

Quoted 1 line · In message <[email protected]> you wrote:
Signed-off-by Larry Johnson <[email protected]>
...
Quoted 2 lines
- * (C) Copyright 2007
+ * (C) Copyright 2007-2008

Quoted 7 lines

If you make a change, how can this change Stefan's Copyright?
Please do not mess with other people's copyrights!
Best regards,
Wolfgang Denk

Sorry, I though that by making the changes I was assigning the rights to the to Stefan (subject to the GPL).

I will resubmit the patches where I did this.

Best regards,
Larry