[PATCH 4/4] [POWERPC] QE: implement support for the GPIO LIB API
Anton Vorontsov
avorontsov at ru.mvista.com
Wed Mar 12 05:42:30 EST 2008
Signed-off-by: Anton Vorontsov <avorontsov at ru.mvista.com>
---
Documentation/powerpc/booting-without-of.txt | 32 ++++---
arch/powerpc/platforms/Kconfig | 2 +
arch/powerpc/sysdev/qe_lib/qe_io.c | 137 +++++++++++++++++++++++++-
3 files changed, 158 insertions(+), 13 deletions(-)
diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
index e9e0c2f..113884b 100644
--- a/Documentation/powerpc/booting-without-of.txt
+++ b/Documentation/powerpc/booting-without-of.txt
@@ -1703,24 +1703,32 @@ platforms are moved over to use the flattened-device-tree model.
information.
Required properties:
- - device_type : should be "par_io".
+ - #gpio-cells : should be "2".
+ - compatible : should be "fsl,qe-pario-bank-<bank>", "fsl,qe-pario-bank"
- reg : offset to the register set and its length.
- - num-ports : number of Parallel I/O ports
+ - gpio-controller : node to identify gpio controllers.
- Example:
- par_io at 1400 {
- reg = <1400 100>;
- #address-cells = <1>;
- #size-cells = <0>;
- device_type = "par_io";
- num-ports = <7>;
- ucc_pin at 01 {
- ......
- };
+ For example, two QE Par I/O banks:
+ qe_pio_a: gpio-controller at 1400 {
+ #gpio-cells = <2>;
+ compatible = "fsl,qe-pario-bank-a", "fsl,qe-pario-bank";
+ reg = <0x1400 0x18>;
+ gpio-controller;
+ };
+ qe_pio_e: gpio-controller at 1460 {
+ #gpio-cells = <2>;
+ compatible = "fsl,qe-pario-bank-e", "fsl,qe-pario-bank";
+ reg = <0x1460 0x18>;
+ gpio-controller;
+ };
vi) Pin configuration nodes
+ NOTE: pin configuration nodes are obsolete. Usually, their existance
+ is an evidence of the firmware shortcomings. Such fixups are
+ better handled by the Linux board file, not the device tree.
+
Required properties:
- linux,phandle : phandle of this node; likely referenced by a QE
device.
diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig
index 0afd225..2d91ed9 100644
--- a/arch/powerpc/platforms/Kconfig
+++ b/arch/powerpc/platforms/Kconfig
@@ -271,6 +271,8 @@ config QUICC_ENGINE
bool
select PPC_LIB_RHEAP
select CRC32
+ select GENERIC_GPIO
+ select HAVE_GPIO_LIB
help
The QUICC Engine (QE) is a new generation of communications
coprocessors on Freescale embedded CPUs (akin to CPM in older chips).
diff --git a/arch/powerpc/sysdev/qe_lib/qe_io.c b/arch/powerpc/sysdev/qe_lib/qe_io.c
index a3f9c3f..a4a195a 100644
--- a/arch/powerpc/sysdev/qe_lib/qe_io.c
+++ b/arch/powerpc/sysdev/qe_lib/qe_io.c
@@ -20,7 +20,8 @@
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/ioport.h>
-
+#include <linux/spinlock.h>
+#include <linux/of_gpio.h>
#include <asm/io.h>
#include <asm/qe.h>
#include <asm/prom.h>
@@ -214,6 +215,140 @@ int par_io_of_config(struct device_node *np)
}
EXPORT_SYMBOL(par_io_of_config);
+/*
+ * GPIO LIB API implementation
+ */
+
+struct qe_gpio_chip {
+ struct of_mm_gpio_chip mm_gc;
+ spinlock_t lock;
+
+ /* shadowed data register to clear/set bits safely */
+ u32 cpdata;
+};
+
+static inline struct qe_gpio_chip *
+to_qe_gpio_chip(struct of_mm_gpio_chip *mm_gc)
+{
+ return container_of(mm_gc, struct qe_gpio_chip, mm_gc);
+}
+
+static void qe_gpio_save_regs(struct of_mm_gpio_chip *mm_gc)
+{
+ struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+ struct port_regs __iomem *regs = mm_gc->regs;
+
+ qe_gc->cpdata = in_be32(®s->cpdata);
+}
+
+static int qe_gpio_get(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct port_regs __iomem *regs = mm_gc->regs;
+ u32 pin_mask;
+
+ /* calculate pin location */
+ pin_mask = (u32) (1 << (NUM_OF_PINS - 1 - gpio));
+
+ return !!(in_be32(®s->cpdata) & pin_mask);
+}
+
+static void qe_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+ struct port_regs __iomem *regs = mm_gc->regs;
+ unsigned long flags;
+ u32 pin_mask = 1 << (NUM_OF_PINS - 1 - gpio);
+
+ spin_lock_irqsave(&qe_gc->lock, flags);
+
+ if (val)
+ qe_gc->cpdata |= pin_mask;
+ else
+ qe_gc->cpdata &= ~pin_mask;
+
+ out_be32(®s->cpdata, qe_gc->cpdata);
+
+ spin_unlock_irqrestore(&qe_gc->lock, flags);
+}
+
+static int qe_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+ unsigned long flags;
+
+ spin_lock_irqsave(&qe_gc->lock, flags);
+
+ __par_io_config_pin(mm_gc->regs, gpio, 2, 0, 0, 0);
+
+ spin_unlock_irqrestore(&qe_gc->lock, flags);
+
+ return 0;
+}
+
+static int qe_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+ unsigned long flags;
+
+ spin_lock_irqsave(&qe_gc->lock, flags);
+
+ __par_io_config_pin(mm_gc->regs, gpio, 1, 0, 0, 0);
+
+ spin_unlock_irqrestore(&qe_gc->lock, flags);
+
+ qe_gpio_set(gc, gpio, val);
+
+ return 0;
+}
+
+static int __init qe_add_gpiochips(void)
+{
+ int ret;
+ struct device_node *np;
+
+ for_each_compatible_node(np, NULL, "fsl,qe-pario-bank") {
+ struct qe_gpio_chip *qe_gc;
+ struct of_mm_gpio_chip *mm_gc;
+ struct of_gpio_chip *of_gc;
+ struct gpio_chip *gc;
+
+ qe_gc = kzalloc(sizeof(*qe_gc), GFP_KERNEL);
+ if (!qe_gc) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ spin_lock_init(&qe_gc->lock);
+
+ mm_gc = &qe_gc->mm_gc;
+ of_gc = &mm_gc->of_gc;
+ gc = &of_gc->gc;
+
+ mm_gc->save_regs = qe_gpio_save_regs;
+ of_gc->gpio_cells = 2;
+ gc->ngpio = NUM_OF_PINS;
+ gc->direction_input = qe_gpio_dir_in;
+ gc->direction_output = qe_gpio_dir_out;
+ gc->get = qe_gpio_get;
+ gc->set = qe_gpio_set;
+
+ ret = of_mm_gpiochip_add(np, mm_gc);
+ if (ret)
+ goto err;
+ }
+
+ return 0;
+err:
+ pr_err("%s: registration failed with status %d\n", np->full_name, ret);
+ of_node_put(np);
+ return ret;
+}
+arch_initcall(qe_add_gpiochips);
+
#ifdef DEBUG
static void dump_par_io(void)
{
--
1.5.2.2
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