[PATCH] drivers: PMC MSP71xx GPIO char driver
Patch to add a GPIO char driver for the PMC-Sierra
MSP71xx devices.
This patch references some platform support files previously
submitted to the [email protected] list.
Thanks,
Marc
Signed-off-by: Marc St-Jean <[email protected]>
---
drivers/char/Kconfig | 4
drivers/char/Makefile | 1
drivers/char/pmcmsp_gpio.c | 587 +++++++++++++++++++++++++
include/asm-mips/pmc-sierra/msp71xx/msp_gpio.h | 164 ++++++
4 files changed, 756 insertions(+)
diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index ed5453f..dea96a0 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -372,6 +372,10 @@ config ISTALLION
To compile this driver as a module, choose M here: the
module will be called istallion.
+config PMCMSP_GPIO
+ tristate "PMC MSP 7120 GPIO device support"
+ depends on MIPS && (PMC_MSP7120_EVAL || PMC_MSP7120_GW || PMC_MSP7120_FPGA)
+
config AU1X00_GPIO
tristate "Alchemy Au1000 GPIO device support"
depends on MIPS && SOC_AU1X00
diff --git a/drivers/char/Makefile b/drivers/char/Makefile
index 3ed7647..9abbcc1 100644
--- a/drivers/char/Makefile
+++ b/drivers/char/Makefile
@@ -86,6 +86,7 @@ obj-$(CONFIG_DS1620) += ds1620.o
obj-$(CONFIG_HW_RANDOM) += hw_random/
obj-$(CONFIG_COBALT_LCD) += lcd.o
obj-$(CONFIG_AU1000_GPIO) += au1000_gpio.o
+obj-$(CONFIG_PMCMSP_GPIO) += pmcmsp_gpio.o
obj-$(CONFIG_PPDEV) += ppdev.o
obj-$(CONFIG_NWBUTTON) += nwbutton.o
obj-$(CONFIG_NWFLASH) += nwflash.o
diff --git a/drivers/char/pmcmsp_gpio.c b/drivers/char/pmcmsp_gpio.c
new file mode 100644
index 0000000..23b48d9
--- /dev/null
+++ b/drivers/char/pmcmsp_gpio.c
@@ -0,0 +1,587 @@
+/*
+ * $Id: pmcmsp_gpio.c,v 1.3 2006/10/19 22:08:16 stjeanma Exp $
+ *
+ * Driver for the PMC MSP7120 reference board GPIO pins
+ *
+ * Copyright 2005 PMC-Sierra, Inc.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/spinlock.h>
+#include <linux/miscdevice.h>
+#include <linux/fs.h>
+#include <linux/kthread.h>
+#include <linux/sched.h>
+#include <linux/completion.h>
+#include <asm/io.h>
+
+#include <asm/war.h>
+#include <asm/regops.h>
+
+#include <msp_regs.h>
+#include <msp_gpio.h>
+
+static DEFINE_SPINLOCK(msp_gpio_spinlock);
+
+static struct task_struct *msp_blinkthread;
+static int msp_blink_running;
+static DEFINE_SPINLOCK(msp_blink_lock);
+static DECLARE_COMPLETION(msp_blink_wait);
+
+struct blinkTable_t {
+ uint32_t count;
+ uint32_t period;
+ uint32_t dcycle;
+};
+
+static struct blinkTable_t blinkTable[MSP_NUM_GPIOS];
+
+/* Define the following for extra debug output */
+#undef DEBUG
+
+/* -- Utility functions -- */
+
+#ifdef DEBUG
+#define DBG(args...) printk( args )
+#else
+#define DBG(args...) do{} while( 0 )
+#endif
+
+/* Reads the data bits from a single register set */
+static uint32_t msp_gpio_read_data_basic( int reg )
+{
+ return *GPIO_DATA_REG[reg] & GPIO_DATA_MASK[reg];
+}
+
+/* Reads the data bits from the extended register set */
+static uint32_t msp_gpio_read_data_extended(void)
+{
+ int pin;
+ uint32_t tmp, retval = 0;
+
+ tmp = *EXTENDED_GPIO_REG;
+ for( pin = 0; pin < EXTENDED_GPIO_COUNT; pin++ ) {
+ uint32_t bit = 0;
+ /*
+ * In output mode, read CLR bit
+ * In input mode, read SET bit
+ */
+ if( tmp & (EXTENDED_GPIO_CFG_ENABLE <<
+ EXTENDED_GPIO_CFG_SHIFT(pin)) )
+ bit = (EXTENDED_GPIO_DATA_CLR <<
+ EXTENDED_GPIO_DATA_SHIFT(pin));
+ else
+ bit = (EXTENDED_GPIO_DATA_SET <<
+ EXTENDED_GPIO_DATA_SHIFT(pin));
+
+ if( tmp & bit )
+ retval |= (1 << pin);
+ }
+ return retval;
+}
+
+/*
+ * Reads the current state of all 20 pins, putting the values in the lowest 20
+ * bits
+ * (1=HI, 0=LO)
+ */
+static uint32_t msp_gpio_read_data(void)
+{
+ int reg;
+ uint32_t retval = 0;
+
+ spin_lock(&msp_gpio_spinlock);
+ for( reg = 0; reg < GPIO_REG_COUNT; reg++ )
+ retval |= msp_gpio_read_data_basic(reg) << GPIO_DATA_SHIFT[reg];
+ retval |= msp_gpio_read_data_extended() << EXTENDED_GPIO_SHIFT;
+ spin_unlock(&msp_gpio_spinlock);
+ DBG( "%s: 0x%08x\n", __FUNCTION__, retval );
+ return retval;
+}
+
+/* This assumes both data and mask are register-ready, and does the set
+ * atomically */
+static void msp_gpio_write_data_basic( int reg, uint32_t data, uint32_t mask )
+{
+ set_value_reg32( GPIO_DATA_REG[reg], mask, data );
+}
+
+/* The four lowest bits of 'data' and 'mask' are used, and the set is done
+ * atomically */
+static void msp_gpio_write_data_extended( uint32_t data, uint32_t mask )
+{
+ int i;
+ uint32_t tmpmask = 0xffffffff, tmpdata = 0;
+
+ /* Set all SET/CLR values based on data bits passed in */
+ for( i = 0; i < EXTENDED_GPIO_COUNT; i++ ) {
+ if( mask & (1 << i) ) {
+ if( data & (1 << i) )
+ /* Set the bit HI */
+ tmpdata |= EXTENDED_GPIO_DATA_SET <<
+ EXTENDED_GPIO_DATA_SHIFT(i);
+ else
+ /* Set the bit LO */
+ tmpdata |= EXTENDED_GPIO_DATA_CLR <<
+ EXTENDED_GPIO_DATA_SHIFT(i);
+ }
+ }
+
+ set_value_reg32( EXTENDED_GPIO_REG, tmpmask, tmpdata );
+}
+
+/*
+ * Sets all masked GPIOs based on the first 20 bits of the data passed in
+ * (1=HI, 0=LO)
+ */
+static void msp_gpio_write_data( uint32_t data, uint32_t mask )
+{
+ int reg;
+
+ spin_lock(&msp_gpio_spinlock);
+ for( reg = 0; reg < GPIO_REG_COUNT; reg++ ) {
+ uint32_t tmpdata = (data >> GPIO_DATA_SHIFT[reg]) &
+ GPIO_DATA_MASK[reg];
+ uint32_t tmpmask = (mask >> GPIO_DATA_SHIFT[reg]) &
+ GPIO_DATA_MASK[reg];
+ if( tmpmask > 0 )
+ msp_gpio_write_data_basic( reg, tmpdata, tmpmask );
+ }
+ msp_gpio_write_data_extended( data >> EXTENDED_GPIO_SHIFT,
+ mask >> EXTENDED_GPIO_SHIFT );
+ spin_unlock(&msp_gpio_spinlock);
+}
+
+/* Reads the config bits from a single register set */
+static uint32_t msp_gpio_read_cfg_basic( int reg )
+{
+ return *GPIO_CFG_REG[reg] & GPIO_CFG_MASK[reg];
+}
+
+/* This assumes both data and mask are register-ready, and does the write
+ * atomically */
+static void msp_gpio_write_cfg_basic( int reg, uint32_t data, uint32_t mask )
+{
+ set_value_reg32( GPIO_CFG_REG[reg], mask, data );
+}
+
+/*
+ * Reads the configuration of the extended pins, returning the current
+ * configuration in the lowest 4 bits (1-output, 0-input)
+ */
+static uint32_t msp_gpio_read_cfg_extended(void)
+{
+ int i;
+ uint32_t tmp = *EXTENDED_GPIO_REG;
+ uint32_t retval = 0;
+
+ /* Read all ENABLE/DISABLE values and translate to single bits */
+ for( i = 0; i < EXTENDED_GPIO_COUNT; i++ ) {
+ if( tmp & (EXTENDED_GPIO_CFG_ENABLE <<
+ EXTENDED_GPIO_CFG_SHIFT(i)) )
+ /* Pin is OUTPUT */
+ retval |= (1 << i);
+ else
+ /* Pin is INPUT */
+ retval &= ~(1 << i);
+ }
+
+ return retval;
+}
+
+/*
+ * Sets the masked extended pins to (1-output, 0-input)
+ * (uses 4 lowest bits of the mask)
+ * Does the write atomically
+ */
+static void msp_gpio_write_cfg_extended( uint32_t data, uint32_t mask )
+{
+ int i;
+ uint32_t tmpmask = 0xffffffff, tmpdata = 0;
+
+ /* Set all ENABLE/DISABLE values based on mask bits passed in */
+ for( i = 0; i < EXTENDED_GPIO_COUNT; i++ ) {
+ if( mask & (1 << i) ) {
+ if( data & (1 << i) )
+ /* Set the pin to OUTPUT */
+ tmpdata |= EXTENDED_GPIO_CFG_ENABLE <<
+ EXTENDED_GPIO_CFG_SHIFT(i);
+ else
+ /* Set the pin to INPUT */
+ tmpdata |= EXTENDED_GPIO_CFG_DISABLE <<
+ EXTENDED_GPIO_CFG_SHIFT(i);
+ }
+ }
+
+ set_value_reg32( EXTENDED_GPIO_REG, tmpmask, tmpdata );
+}
+
+/*
+ * Sets all GPIOs to input/output based on the first 20 bits of the mask
+ * (1-output, 0-input)
+ */
+static void msp_gpio_write_cfg( msp_gpio_mode_t mode, uint32_t mask )
+{
+ int reg;
+ uint32_t extdata = 0, extmask = 0;
+
+ spin_lock(&msp_gpio_spinlock);
+ for( reg = 0; reg < GPIO_REG_COUNT; reg++ ) {
+ int pin;
+ uint32_t tmpdata = 0, tmpmask = 0;
+ for( pin = 0; pin < GPIO_DATA_COUNT[reg]; pin++ ) {
+ if( mask & (1 << (GPIO_DATA_SHIFT[reg] + pin)) ) {
+ tmpmask |= (GPIO_CFG_PINMASK <<
+ GPIO_CFG_SHIFT(pin) );
+ tmpdata |= ( (uint32_t)mode <<
+ GPIO_CFG_SHIFT(pin) );
+ }
+ }
+ if( tmpmask )
+ msp_gpio_write_cfg_basic(reg, tmpdata, tmpmask);
+ }
+
+ extmask = mask >> EXTENDED_GPIO_SHIFT;
+ if( mode == MSP_GPIO_INPUT )
+ extdata = 0;
+ else if( mode == MSP_GPIO_OUTPUT )
+ extdata = 0xf;
+ else
+ extmask = 0;
+ if( extmask )
+ msp_gpio_write_cfg_extended( extdata, extmask );
+ spin_unlock(&msp_gpio_spinlock);
+}
+
+/*
+ * Reads all GPIO config values and checks if they match the pin mode given,
+ * placing the result in the lowest 20 bits of the result, one bit per pin
+ * (1-pin matches mode give, 0-pin does not match)
+ */
+static uint32_t msp_gpio_read_cfg( uint32_t mode )
+{
+ uint32_t retval = 0;
+ int reg;
+
+ spin_lock(&msp_gpio_spinlock);
+ for( reg = 0; reg < GPIO_REG_COUNT; reg++ ) {
+ int pin;
+ uint32_t tmpdata = msp_gpio_read_cfg_basic(reg);
+ for( pin = 0; pin < GPIO_DATA_COUNT[reg]; pin++ ) {
+ uint32_t val = (tmpdata >> GPIO_CFG_SHIFT(pin)) &
+ GPIO_CFG_PINMASK;
+ if( val == mode )
+ retval |= (1 << (GPIO_DATA_SHIFT[reg] + pin));
+ }
+ }
+ /* Extended pins only have INPUT or OUTPUT pins */
+ if( mode == MSP_GPIO_INPUT )
+ retval |= (~msp_gpio_read_cfg_extended() & EXTENDED_GPIO_MASK)
+ << EXTENDED_GPIO_SHIFT;
+ else if( mode == MSP_GPIO_OUTPUT )
+ retval |= (msp_gpio_read_cfg_extended() & EXTENDED_GPIO_MASK)
+ << EXTENDED_GPIO_SHIFT;
+ spin_unlock(&msp_gpio_spinlock);
+ DBG( "%s(0x%02x): 0x%08x\n", __FUNCTION__, mode, retval );
+ return retval;
+}
+
+/* -- Public functions -- */
+
+/*
+ * Reads the bits specified by the mask and puts the values in data.
+ * May include output statuses also, if in mask.
+ *
+ * Returns 0 on success
+ */
+int msp_gpio_in( uint32_t *data, uint32_t mask )
+{
+ *data = msp_gpio_read_data() & mask;
+ return 0;
+}
+
+/*
+ * Sets the pins to output with the specified data on them
+ *
+ * Returns 0 on success or one of the following:
+ * -EINVAL if any of the pins in the mask are not free
+ */
+int msp_gpio_out( uint32_t data, uint32_t mask )
+{
+ if( (mask & ~MSP_GPIO_FREE_MASK) != 0 ) {
+ printk( "Invalid GPIO mask - References non-free pins\n" );
+ return -EINVAL;
+ }
+ if( (mask & ~msp_gpio_read_cfg(MSP_GPIO_OUTPUT)) != 0 ) {
+ printk( "Invalid GPIO mask - Cannot set non-output pins\n" );
+ return -EINVAL;
+ }
+
+ msp_gpio_noblink( mask );
+ msp_gpio_write_data( data, mask );
+
+ return 0;
+}
+
+/*
+ * Sets the pins to output or input (1 is output, 0 is input)
+ *
+ * Returns 0 on success or one of the following:
+ * -EINVAL if any of the pins in the mask are not free
+ */
+int msp_gpio_mode( msp_gpio_mode_t mode, uint32_t mask )
+{
+ uint32_t allowedmask;
+
+ if( (mask & ~MSP_GPIO_FREE_MASK) != 0 ) {
+ printk( "Invalid GPIO mask - References non-free pins\n" );
+ return -EINVAL;
+ }
+
+ /* Enforce pin-mode rules */
+ allowedmask = MSP_GPIO_MODE_ALLOWED[mode];
+ if( (mask & ~allowedmask) != 0 ) {
+ printk( "Invalid GPIO mode for masked pins\n" );
+ return -EINVAL;
+ }
+
+ msp_gpio_noblink( mask );
+ msp_gpio_write_cfg( mode, mask );
+
+ return 0;
+}
+
+/*
+ * Stops the specified GPIOs from blinking
+ */
+int msp_gpio_noblink( uint32_t mask )
+{
+ int i;
+
+ if( (mask & ~msp_gpio_read_cfg(MSP_GPIO_OUTPUT)) != 0 )
+ return -EINVAL;
+
+ spin_lock( &msp_blink_lock );
+ for( i = 0; i < MSP_NUM_GPIOS; i++ ) {
+ if( mask & MSP_GPIO_BIT(i) ) {
+ blinkTable[i].count = 0;
+ blinkTable[i].period = 0;
+ blinkTable[i].dcycle = 0;
+ }
+ }
+ spin_unlock( &msp_blink_lock );
+
+ msp_gpio_write_data( 0, mask );
+
+ return 0;
+}
+
+/*
+ * Configures GPIO(s) to blink
+ * - mask shows which GPIOs to blink
+ * - period is the time in 100ths of a second for the total period
+ * (0 disables blinking)
+ * - dcycle is the percentage of the period where the GPIO is HI
+ */
+int msp_gpio_blink( uint32_t mask, uint32_t period, uint32_t dcycle )
+{
+ int i;
+
+ if( (mask & ~msp_gpio_read_cfg(MSP_GPIO_OUTPUT)) != 0 ) {
+ printk( "Invalid GPIO mask - Cannot blink non-output pins\n" );
+ return -EINVAL;
+ }
+
+ if( period == 0 )
+ return msp_gpio_noblink( mask );
+
+ spin_lock( &msp_blink_lock );
+ for( i = 0; i < MSP_NUM_GPIOS; i++ ) {
+ if( mask & MSP_GPIO_BIT(i) ) {
+ blinkTable[i].count = 0;
+ blinkTable[i].period = period;
+ blinkTable[i].dcycle = dcycle;
+ }
+ }
+ spin_unlock( &msp_blink_lock );
+
+ complete( &msp_blink_wait );
+
+ return 0;
+}
+
+/* -- File functions -- */
+static int msp_gpio_open( struct inode *inode, struct file *file )
+{
+ return 0;
+}
+
+static int msp_gpio_release( struct inode *inode, struct file *file )
+{
+ return 0;
+}
+
+static int msp_gpio_ioctl( struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ static struct msp_gpio_ioctl_io_data data;
+ static struct msp_gpio_ioctl_blink_data blink;
+
+ switch( cmd ) {
+ case MSP_GPIO_BLINK:
+ if( copy_from_user(&blink, (struct msp_gpio_ioctl_blink_data *)arg, sizeof(blink) ) )
+ return -EFAULT;
+ break;
+ default:
+ if( copy_from_user(&data, (struct msp_gpio_ioctl_io_data *)arg, sizeof(data) ) )
+ return -EFAULT;
+ break;
+ }
+
+ switch( cmd ) {
+ case MSP_GPIO_IN:
+ if( msp_gpio_in( &data.data, data.mask ) )
+ return -EFAULT;
+ if( copy_to_user( (struct msp_gpio_ioctl_io_data *)arg, &data, sizeof(data)) )
+ return -EFAULT;
+ break;
+ case MSP_GPIO_OUT:
+ if( msp_gpio_out( data.data, data.mask ) )
+ return -EFAULT;
+ break;
+ case MSP_GPIO_MODE:
+ if( msp_gpio_mode( data.data, data.mask ) )
+ return -EFAULT;
+ break;
+ case MSP_GPIO_BLINK:
+ if( msp_gpio_blink( blink.mask, blink.period, blink.dcycle ) )
+ return -EFAULT;
+ break;
+ default:
+ return -ENOIOCTLCMD;
+ }
+ return 0;
+}
+
+static struct file_operations msp_gpio_fops = {
+ .owner = THIS_MODULE,
+ .ioctl = msp_gpio_ioctl,
+ .open = msp_gpio_open,
+ .release = msp_gpio_release,
+};
+
+static struct miscdevice msp_gpio_miscdev = {
+ MISC_DYNAMIC_MINOR,
+ "pmcmsp_gpio",
+ &msp_gpio_fops
+};
+
+/* -- Module functions -- */
+
+static int msp_gpio_blinkthread( void *none )
+{
+ int firstrun = 1;
+
+ msp_blink_running = 1;
+ while( msp_blink_running ) {
+ uint32_t mask = 0, data = 0;
+ int i, blinking = 0;
+ spin_lock( &msp_blink_lock );
+ for( i = 0; i < MSP_NUM_GPIOS; i++ ) {
+ /* use blinkTable[i].period as 'blink enabled' test */
+ if( blinkTable[i].period) {
+ blinking = 1;
+ mask |= MSP_GPIO_BIT(i);
+ blinkTable[i].count++;
+
+ if( blinkTable[i].count >=
+ blinkTable[i].period )
+ blinkTable[i].count = 0;
+
+ if( blinkTable[i].count <
+ (blinkTable[i].period *
+ blinkTable[i].dcycle / 100 ) )
+ data |= MSP_GPIO_BIT(i);
+ }
+ }
+ spin_unlock( &msp_blink_lock );
+
+ if( !firstrun || blinking )
+ msp_gpio_write_data( data, mask );
+ else
+ firstrun = 0;
+
+ if( blinking ) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout (HZ/100);
+ } else {
+ wait_for_completion_interruptible( &msp_blink_wait );
+ }
+ }
+
+ return 0;
+}
+
+static int __init msp_gpio_init(void)
+{
+ if( misc_register(&msp_gpio_miscdev) ) {
+ printk( "Device registration failed\n" );
+ goto err_miscdev;
+ }
+
+ msp_blinkthread = kthread_run( msp_gpio_blinkthread, NULL, "gpio_blink" );
+ if( msp_blinkthread == NULL )
+ {
+ printk( "Could not start kthread\n" );
+ goto err_blinkthread;
+ }
+
+ printk( "MSP7120 GPIO subsystem initialized\n" );
+ return 0;
+
+err_blinkthread:
+ misc_deregister(&msp_gpio_miscdev);
+err_miscdev:
+ return -ENOMEM;
+}
+
+static void __exit msp_gpio_exit(void)
+{
+ msp_blink_running = 0;
+ complete( &msp_blink_wait );
+ kthread_stop( msp_blinkthread );
+
+ misc_deregister(&msp_gpio_miscdev);
+}
+
+module_init(msp_gpio_init);
+module_exit(msp_gpio_exit);
+
+EXPORT_SYMBOL(msp_gpio_in);
+EXPORT_SYMBOL(msp_gpio_out);
+EXPORT_SYMBOL(msp_gpio_mode);
+EXPORT_SYMBOL(msp_gpio_blink);
+EXPORT_SYMBOL(msp_gpio_noblink);
+
+MODULE_LICENSE("GPL");
diff --git a/include/asm-mips/pmc-sierra/msp71xx/msp_gpio.h b/include/asm-mips/pmc-sierra/msp71xx/msp_gpio.h
new file mode 100644
index 0000000..7459355
--- /dev/null
+++ b/include/asm-mips/pmc-sierra/msp71xx/msp_gpio.h
@@ -0,0 +1,164 @@
+/*
+ * $Id: msp_gpio.h,v 1.4 2006/05/08 19:45:39 ramsayji Exp $
+ *
+ * Character driver for the PMC Athena (MSP7120) reference board GPIO pins
+ *
+ * Copyright 2005 PMC-Sierra, Inc.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef __MSP_GPIO_H__
+#define __MSP_GPIO_H__
+
+#include <linux/ioctl.h>
+#include <msp_gpio_macros.h>
+
+/* IOCTL structs macros */
+
+struct msp_gpio_ioctl_io_data
+{
+ uint32_t data;
+ uint32_t mask;
+};
+
+struct msp_gpio_ioctl_blink_data
+{
+ uint32_t mask;
+ uint32_t period;
+ uint32_t dcycle;
+};
+
+#define MSP_GPIO_IOCTL_BASE 'Z'
+
+/* Reads the current data bits */
+#define MSP_GPIO_IN _IOWR(MSP_GPIO_IOCTL_BASE, 0, \
+ struct msp_gpio_ioctl_io_data )
+
+/* Writes data bits */
+#define MSP_GPIO_OUT _IOW (MSP_GPIO_IOCTL_BASE, 1, \
+ struct msp_gpio_ioctl_io_data )
+
+/*
+ * Sets all masked pins to the msp_gpio_mode_t given in the data field
+ */
+#define MSP_GPIO_MODE _IOW (MSP_GPIO_IOCTL_BASE, 2, \
+ struct msp_gpio_ioctl_io_data )
+
+/*
+ * Starts any masked LEDs blinking with parameters as follows:
+ * - period - The time in 100ths of a second for a single period
+ * (set to '0' to stop blinking)
+ * - dcycle - The 'duty cycle' - what percentage of the period should the
+ * gpio be on?
+ */
+#define MSP_GPIO_BLINK _IOW (MSP_GPIO_IOCTL_BASE, 3, \
+ struct msp_gpio_ioctl_blink_data )
+
+/* Bit flags and masks for GPIOs */
+#define MSP_GPIO_BIT(gpio) (1 << gpio)
+
+#define MSP_NUM_GPIOS (20)
+
+#define MSP_GPIO_ALL_MASK ((1<<MSP_NUM_GPIOS) - 1)
+
+#define MSP_GPIO_NONE_MASK (0LL)
+
+#define MSP_GPIO_FREE_MASK MSP_GPIO_ALL_MASK
+
+/* The following is only available to other modules */
+
+#ifdef __KERNEL__
+
+/*
+ * Reads the bits specified by the mask and puts the values in data.
+ * May include output statuses also, if in mask.
+ *
+ * Returns 0 on success
+ */
+extern int msp_gpio_in( uint32_t *data, uint32_t mask );
+
+/*
+ * Sets the specified data to the masked pins
+ *
+ * Returns 0 on success or one of the following:
+ * -EINVAL if any of the pins in the mask are not free or not already in output
+ * mode
+ */
+extern int msp_gpio_out( uint32_t data, uint32_t mask );
+
+/*
+ * Sets all masked pins to the specified msp_gpio_mode_t
+ *
+ * Returns 0 on success or one of the following:
+ * -EINVAL if any of the pins in the mask are not free, or if any pins are not
+ * allowed to be set to the specified mode
+ */
+extern int msp_gpio_mode( msp_gpio_mode_t mode, uint32_t mask );
+
+/*
+ * Stops the specified GPIOs from blinking
+ */
+extern int msp_gpio_noblink( uint32_t mask );
+
+/*
+ * Configures GPIO(s) to blink
+ * - mask shows which GPIOs to blink
+ * - period is the time in 100ths of a second for the total period
+ * (0 disables blinking)
+ * - dcycle is the percentage of the period where the GPIO is HI
+ */
+int msp_gpio_blink( uint32_t mask, uint32_t period, uint32_t dcycle );
+
+/* Special bitflags and whatnot for the driver's convenience */
+#define GPIO_REG_COUNT 4
+const uint32_t GPIO_DATA_COUNT[] = { 2, 4, 4, 6 };
+const uint32_t GPIO_DATA_SHIFT[] = { 0, 2, 6, 10 };
+const uint32_t GPIO_DATA_MASK[] = { 0x03, 0x0f, 0x0f, 0x3f };
+volatile uint32_t * const GPIO_DATA_REG[] = {
+ GPIO_DATA1_REG, GPIO_DATA2_REG, GPIO_DATA3_REG, GPIO_DATA4_REG,
+};
+const uint32_t GPIO_CFG_MASK[] = { 0x0000ff, 0x00ffff, 0x00ffff, 0xffffff };
+volatile uint32_t * const GPIO_CFG_REG[] = {
+ GPIO_CFG1_REG, GPIO_CFG2_REG, GPIO_CFG3_REG, GPIO_CFG4_REG,
+};
+
+#define GPIO_CFG_SHIFT(i) (i * 4)
+#define GPIO_CFG_PINMASK 0xf
+
+/* The extra-weird extended gpio register */
+
+#define EXTENDED_GPIO_COUNT 4
+#define EXTENDED_GPIO_SHIFT 16
+#define EXTENDED_GPIO_MASK 0x0f
+
+#define EXTENDED_GPIO_DATA_SHIFT(i) (i * 2)
+#define EXTENDED_GPIO_DATA_MASK(i) (0x3 << (i*2))
+#define EXTENDED_GPIO_DATA_SET 0x2
+#define EXTENDED_GPIO_DATA_CLR 0x1
+#define EXTENDED_GPIO_CFG_SHIFT(i) ((i * 2) + 16)
+#define EXTENDED_GPIO_CFG_MASK(i) (0x3 << ((i*2)+16))
+#define EXTENDED_GPIO_CFG_DISABLE 0x2
+#define EXTENDED_GPIO_CFG_ENABLE 0x1
+
+#endif /* __KERNEL__ */
+
+#endif /* __MSP_GPIO_H__ */
> On Fri, 23 Feb 2007 17:28:19 -0600 Marc St-Jean <[email protected]> wrote:
> [PATCH] drivers: PMC MSP71xx GPIO char driver
>
> Patch to add a GPIO char driver for the PMC-Sierra
> MSP71xx devices.
>
> This patch references some platform support files previously
> submitted to the [email protected] list.
>
Comments:
> +static int msp_blink_running;
Could have type `bool'.
> +static DEFINE_SPINLOCK(msp_blink_lock);
> +static DECLARE_COMPLETION(msp_blink_wait);
> +
> +struct blinkTable_t {
a) It uses StudlyCaps
b) the _t suffix is used for typedefs.
I suggest this be renamed to `struct blink_table'.
> + uint32_t count;
> + uint32_t period;
> + uint32_t dcycle;
u32 is preferred.
> +static uint32_t msp_gpio_read_data_extended(void)
everywhere...
> +{
> + int pin;
> + uint32_t tmp, retval = 0;
> +
> + tmp = *EXTENDED_GPIO_REG;
> + for( pin = 0; pin < EXTENDED_GPIO_COUNT; pin++ ) {
> + uint32_t bit = 0;
> + /*
> + * In output mode, read CLR bit
> + * In input mode, read SET bit
> + */
> + if( tmp & (EXTENDED_GPIO_CFG_ENABLE <<
> + EXTENDED_GPIO_CFG_SHIFT(pin)) )
Please convert all the code to sue standard whitespace conventions:
for (i = 0; i < n; i++) {
and
if (foo && bar)
> + bit = (EXTENDED_GPIO_DATA_CLR <<
> + EXTENDED_GPIO_DATA_SHIFT(pin));
Uneeded parens.
> + retval |= (1 << pin);
Ditto.
> +static int msp_gpio_ioctl( struct inode *inode, struct file *file,
> + unsigned int cmd, unsigned long arg)
> +{
> + static struct msp_gpio_ioctl_io_data data;
> + static struct msp_gpio_ioctl_blink_data blink;
> +
> + switch( cmd ) {
switch (cmd) {
> + case MSP_GPIO_BLINK:
> + if( copy_from_user(&blink, (struct msp_gpio_ioctl_blink_data *)arg, sizeof(blink) ) )
> + return -EFAULT;
> + break;
> + default:
> + if( copy_from_user(&data, (struct msp_gpio_ioctl_io_data *)arg, sizeof(data) ) )
> + return -EFAULT;
> + break;
Please indent the body of the switch one tabstop less than this.
Please fit all the code into 80-cols.
> + }
> +
> + switch( cmd ) {
> + case MSP_GPIO_IN:
> + if( msp_gpio_in( &data.data, data.mask ) )
Lots of dittos here.
> +/* -- Module functions -- */
> +
> +static int msp_gpio_blinkthread( void *none )
Why is this a "module function"?
> +{
> + int firstrun = 1;
> +
> + msp_blink_running = 1;
> + while( msp_blink_running ) {
> + uint32_t mask = 0, data = 0;
> + int i, blinking = 0;
> + spin_lock( &msp_blink_lock );
> + for( i = 0; i < MSP_NUM_GPIOS; i++ ) {
> + /* use blinkTable[i].period as 'blink enabled' test */
> + if( blinkTable[i].period) {
> + blinking = 1;
> + mask |= MSP_GPIO_BIT(i);
> + blinkTable[i].count++;
> +
> + if( blinkTable[i].count >=
> + blinkTable[i].period )
> + blinkTable[i].count = 0;
> +
> + if( blinkTable[i].count <
> + (blinkTable[i].period *
> + blinkTable[i].dcycle / 100 ) )
> + data |= MSP_GPIO_BIT(i);
> + }
> + }
> + spin_unlock( &msp_blink_lock );
> +
> + if( !firstrun || blinking )
> + msp_gpio_write_data( data, mask );
> + else
> + firstrun = 0;
> +
> + if( blinking ) {
> + set_current_state(TASK_INTERRUPTIBLE);
> + schedule_timeout (HZ/100);
schedule_timeout_interruptible), or ssleep().
This kernel thread will probably break suspend. I suspect a
try_to_freeze() is needed.
> + } else {
> + wait_for_completion_interruptible( &msp_blink_wait );
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int __init msp_gpio_init(void)
> +{
> + if( misc_register(&msp_gpio_miscdev) ) {
> + printk( "Device registration failed\n" );
> + goto err_miscdev;
> + }
> +
> + msp_blinkthread = kthread_run( msp_gpio_blinkthread, NULL, "gpio_blink" );
> + if( msp_blinkthread == NULL )
> + {
if (msp_blinkthread == NULL) {
> + printk( "Could not start kthread\n" );
> + goto err_blinkthread;
> + }
> +
> + printk( "MSP7120 GPIO subsystem initialized\n" );
Please give all the printks a facility level (KERN_INFO, etc)
> + return 0;
> +
> +err_blinkthread:
> + misc_deregister(&msp_gpio_miscdev);
> +err_miscdev:
> + return -ENOMEM;
> +}
> +
> +static void __exit msp_gpio_exit(void)
> +{
> + msp_blink_running = 0;
> + complete( &msp_blink_wait );
> + kthread_stop( msp_blinkthread );
> +
> + misc_deregister(&msp_gpio_miscdev);
> +}
I think msp_blink_running can just be removed - use kthread_should_stop().
> +module_init(msp_gpio_init);
> +module_exit(msp_gpio_exit);
> +
> +EXPORT_SYMBOL(msp_gpio_in);
> +EXPORT_SYMBOL(msp_gpio_out);
> +EXPORT_SYMBOL(msp_gpio_mode);
> +EXPORT_SYMBOL(msp_gpio_blink);
> +EXPORT_SYMBOL(msp_gpio_noblink);
What uses these exports?
> +#include <msp_gpio_macros.h>
> +
> +/* IOCTL structs macros */
> +
> +struct msp_gpio_ioctl_io_data
struct foo {
> +{
> + uint32_t data;
> + uint32_t mask;
> +};
> +
> +struct msp_gpio_ioctl_blink_data
> +{
Ditto.
> + uint32_t mask;
> + uint32_t period;
> + uint32_t dcycle;
> +};
> +
> +#define MSP_GPIO_IOCTL_BASE 'Z'
> +
> +/* Reads the current data bits */
> +#define MSP_GPIO_IN _IOWR(MSP_GPIO_IOCTL_BASE, 0, \
> + struct msp_gpio_ioctl_io_data )
Remvove space before the )
> +
> +/* Writes data bits */
> +#define MSP_GPIO_OUT _IOW (MSP_GPIO_IOCTL_BASE, 1, \
> + struct msp_gpio_ioctl_io_data )
> +
> +/*
> + * Sets all masked pins to the msp_gpio_mode_t given in the data field
> + */
> +#define MSP_GPIO_MODE _IOW (MSP_GPIO_IOCTL_BASE, 2, \
> + struct msp_gpio_ioctl_io_data )
Dittoes.
> +/*
> + * Starts any masked LEDs blinking with parameters as follows:
> + * - period - The time in 100ths of a second for a single period
> + * (set to '0' to stop blinking)
> + * - dcycle - The 'duty cycle' - what percentage of the period should the
> + * gpio be on?
> + */
> +#define MSP_GPIO_BLINK _IOW (MSP_GPIO_IOCTL_BASE, 3, \
> + struct msp_gpio_ioctl_blink_data )
And remove space before (
> +/* Bit flags and masks for GPIOs */
> +#define MSP_GPIO_BIT(gpio) (1 << gpio)
This probably obscures more than it reveals. Better to open-code it.
> +#define MSP_NUM_GPIOS (20)
> +
> +#define MSP_GPIO_ALL_MASK ((1<<MSP_NUM_GPIOS) - 1)
> +
> +#define MSP_GPIO_NONE_MASK (0LL)
> +
> +#define MSP_GPIO_FREE_MASK MSP_GPIO_ALL_MASK
> +
> +/* The following is only available to other modules */
> +
> +#ifdef __KERNEL__
> +
> +/*
> + * Reads the bits specified by the mask and puts the values in data.
> + * May include output statuses also, if in mask.
> + *
> + * Returns 0 on success
> + */
> +extern int msp_gpio_in( uint32_t *data, uint32_t mask );
Busted whitespace, use u32
> +
> +/*
> + * Sets the specified data to the masked pins
> + *
> + * Returns 0 on success or one of the following:
> + * -EINVAL if any of the pins in the mask are not free or not already in output
> + * mode
> + */
> +extern int msp_gpio_out( uint32_t data, uint32_t mask );
> +
> +/*
> + * Sets all masked pins to the specified msp_gpio_mode_t
> + *
> + * Returns 0 on success or one of the following:
> + * -EINVAL if any of the pins in the mask are not free, or if any pins are not
> + * allowed to be set to the specified mode
> + */
> +extern int msp_gpio_mode( msp_gpio_mode_t mode, uint32_t mask );
It's more conventional to document functions in the .c file, using
kerneldoc format.
> +/*
> + * Stops the specified GPIOs from blinking
> + */
> +extern int msp_gpio_noblink( uint32_t mask );
> +
> +/*
> + * Configures GPIO(s) to blink
> + * - mask shows which GPIOs to blink
> + * - period is the time in 100ths of a second for the total period
> + * (0 disables blinking)
> + * - dcycle is the percentage of the period where the GPIO is HI
> + */
> +int msp_gpio_blink( uint32_t mask, uint32_t period, uint32_t dcycle );
> +
> +/* Special bitflags and whatnot for the driver's convenience */
> +#define GPIO_REG_COUNT 4
> +const uint32_t GPIO_DATA_COUNT[] = { 2, 4, 4, 6 };
> +const uint32_t GPIO_DATA_SHIFT[] = { 0, 2, 6, 10 };
> +const uint32_t GPIO_DATA_MASK[] = { 0x03, 0x0f, 0x0f, 0x3f };
> +volatile uint32_t * const GPIO_DATA_REG[] = {
> + GPIO_DATA1_REG, GPIO_DATA2_REG, GPIO_DATA3_REG, GPIO_DATA4_REG,
> +};
> +const uint32_t GPIO_CFG_MASK[] = { 0x0000ff, 0x00ffff, 0x00ffff, 0xffffff };
> +volatile uint32_t * const GPIO_CFG_REG[] = {
> + GPIO_CFG1_REG, GPIO_CFG2_REG, GPIO_CFG3_REG, GPIO_CFG4_REG,
> +};
This should all be moved from .h into .c. As it is, if two .c files
include this header, we'll get additional copies of this data. And a
linker error.
Please don't use volatile. Kernel standard I/O operations (inb, readl,
etc) handle all this.