[PATCH 4/5] [POWERPC] QE: implement support for the GPIO LIB API
Anton Vorontsov
avorontsov at ru.mvista.com
Sat Apr 19 05:09:59 EST 2008
This is needed to access QE GPIOs via Linux GPIO API.
Signed-off-by: Anton Vorontsov <avorontsov at ru.mvista.com>
---
On Thu, Apr 17, 2008 at 09:21:40PM -0500, Kumar Gala wrote:
>
> On Apr 17, 2008, at 5:41 PM, Anton Vorontsov wrote:
>> On Thu, Apr 17, 2008 at 05:35:53PM -0500, Kumar Gala wrote:
>>>> 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);
>>>
>>> can we split this out into a new file since its pretty much a driver.
>>
>> No problem. Would you prefer this to go under drivers/gpio/ ?
>
>
> Yes that would be better. We actively worked on pull drivers out of
> arch/ppc back in the day.
Hi David,
Do we need your Ack to go this through powerpc tree, and if so, could
you provide one?
Thanks.
Documentation/powerpc/booting-without-of.txt | 34 ++++---
arch/powerpc/platforms/Kconfig | 2 +
drivers/gpio/Kconfig | 9 ++
drivers/gpio/Makefile | 1 +
drivers/gpio/qe.c | 147 ++++++++++++++++++++++++++
5 files changed, 180 insertions(+), 13 deletions(-)
create mode 100644 drivers/gpio/qe.c
diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
index 827b630..5c9cfab 100644
--- a/Documentation/powerpc/booting-without-of.txt
+++ b/Documentation/powerpc/booting-without-of.txt
@@ -1721,24 +1721,32 @@ 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 f38c50b..f6eecd1 100644
--- a/arch/powerpc/platforms/Kconfig
+++ b/arch/powerpc/platforms/Kconfig
@@ -270,6 +270,8 @@ 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/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index bbd2834..cee56f9 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -25,6 +25,15 @@ config DEBUG_GPIO
# put expanders in the right section, in alphabetical order
+comment "On-chip GPIOs:"
+
+config GPIO_QE
+ bool "QUICC Engine GPIOs"
+ depends on QUICC_ENGINE
+ help
+ Say Y here to use GPIOs on the Freescale PowerPC CPUs with
+ QUICC Engine block.
+
comment "I2C GPIO expanders:"
config GPIO_PCA953X
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index fdde992..fd0a41f 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_HAVE_GPIO_LIB) += gpiolib.o
obj-$(CONFIG_GPIO_MCP23S08) += mcp23s08.o
obj-$(CONFIG_GPIO_PCA953X) += pca953x.o
obj-$(CONFIG_GPIO_PCF857X) += pcf857x.o
+obj-$(CONFIG_GPIO_QE) += qe.o
diff --git a/drivers/gpio/qe.c b/drivers/gpio/qe.c
new file mode 100644
index 0000000..474bc44
--- /dev/null
+++ b/drivers/gpio/qe.c
@@ -0,0 +1,147 @@
+/*
+ * QUICC Engine GPIOs
+ *
+ * Copyright (c) MontaVista Software, Inc. 2008.
+ *
+ * Author: Anton Vorontsov <avorontsov at ru.mvista.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/gpio.h>
+#include <asm/qe.h>
+
+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 qe_pio_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 qe_pio_regs __iomem *regs = mm_gc->regs;
+ u32 pin_mask = 1 << (QE_PIO_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 qe_pio_regs __iomem *regs = mm_gc->regs;
+ unsigned long flags;
+ u32 pin_mask = 1 << (QE_PIO_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 = QE_PIO_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);
--
1.5.5
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