diff options
Diffstat (limited to 'Documentation/blackfin')
| -rw-r--r-- | Documentation/blackfin/00-INDEX | 8 | ||||
| -rw-r--r-- | Documentation/blackfin/Makefile | 6 | ||||
| -rw-r--r-- | Documentation/blackfin/bfin-gpio-notes.txt | 71 | ||||
| -rw-r--r-- | Documentation/blackfin/bfin-spi-notes.txt | 16 | ||||
| -rw-r--r-- | Documentation/blackfin/gptimers-example.c | 83 |
5 files changed, 0 insertions, 184 deletions
diff --git a/Documentation/blackfin/00-INDEX b/Documentation/blackfin/00-INDEX deleted file mode 100644 index 2df0365f2df..00000000000 --- a/Documentation/blackfin/00-INDEX +++ /dev/null @@ -1,8 +0,0 @@ -00-INDEX - - This file - -bfin-gpio-notes.txt - - Notes in developing/using bfin-gpio driver. - -bfin-spi-notes.txt - - Notes for using bfin spi bus driver. diff --git a/Documentation/blackfin/Makefile b/Documentation/blackfin/Makefile deleted file mode 100644 index 773dbb103f1..00000000000 --- a/Documentation/blackfin/Makefile +++ /dev/null @@ -1,6 +0,0 @@ -obj-m := gptimers-example.o - -all: modules - -modules clean: - $(MAKE) -C ../.. SUBDIRS=$(PWD) $@ diff --git a/Documentation/blackfin/bfin-gpio-notes.txt b/Documentation/blackfin/bfin-gpio-notes.txt deleted file mode 100644 index d245f39c3d0..00000000000 --- a/Documentation/blackfin/bfin-gpio-notes.txt +++ /dev/null @@ -1,71 +0,0 @@ -/* - * File: Documentation/blackfin/bfin-gpio-notes.txt - * Based on: - * Author: - * - * Created: $Id: bfin-gpio-note.txt 2008-11-24 16:42 grafyang $ - * Description: This file contains the notes in developing/using bfin-gpio. - * - * - * Rev: - * - * Modified: - * Copyright 2004-2008 Analog Devices Inc. - * - * Bugs: Enter bugs at http://blackfin.uclinux.org/ - * - */ - - -1. Blackfin GPIO introduction - - There are many GPIO pins on Blackfin. Most of these pins are muxed to - multi-functions. They can be configured as peripheral, or just as GPIO, - configured to input with interrupt enabled, or output. - - For detailed information, please see "arch/blackfin/kernel/bfin_gpio.c", - or the relevant HRM. - - -2. Avoiding resource conflict - - Followed function groups are used to avoiding resource conflict, - - Use the pin as peripheral, - int peripheral_request(unsigned short per, const char *label); - int peripheral_request_list(const unsigned short per[], const char *label); - void peripheral_free(unsigned short per); - void peripheral_free_list(const unsigned short per[]); - - Use the pin as GPIO, - int bfin_gpio_request(unsigned gpio, const char *label); - void bfin_gpio_free(unsigned gpio); - - Use the pin as GPIO interrupt, - int bfin_gpio_irq_request(unsigned gpio, const char *label); - void bfin_gpio_irq_free(unsigned gpio); - - The request functions will record the function state for a certain pin, - the free functions will clear its function state. - Once a pin is requested, it can't be requested again before it is freed by - previous caller, otherwise kernel will dump stacks, and the request - function fail. - These functions are wrapped by other functions, most of the users need not - care. - - -3. But there are some exceptions - - Kernel permit the identical GPIO be requested both as GPIO and GPIO - interrupt. - Some drivers, like gpio-keys, need this behavior. Kernel only print out - warning messages like, - bfin-gpio: GPIO 24 is already reserved by gpio-keys: BTN0, and you are -configuring it as IRQ! - - Note: Consider the case that, if there are two drivers need the - identical GPIO, one of them use it as GPIO, the other use it as - GPIO interrupt. This will really cause resource conflict. So if - there is any abnormal driver behavior, please check the bfin-gpio - warning messages. - - - Kernel permit the identical GPIO be requested from the same driver twice. - - - diff --git a/Documentation/blackfin/bfin-spi-notes.txt b/Documentation/blackfin/bfin-spi-notes.txt deleted file mode 100644 index eae6eaf2a09..00000000000 --- a/Documentation/blackfin/bfin-spi-notes.txt +++ /dev/null @@ -1,16 +0,0 @@ -SPI Chip Select behavior: - -With the Blackfin on-chip SPI peripheral, there is some logic tied to the CPHA -bit whether the Slave Select Line is controlled by hardware (CPHA=0) or -controlled by software (CPHA=1). However, the Linux SPI bus driver assumes that -the Slave Select is always under software control and being asserted during -the entire SPI transfer. - And not just bits_per_word duration. - -In most cases you can utilize SPI MODE_3 instead of MODE_0 to work-around this -behavior. If your SPI slave device in question requires SPI MODE_0 or MODE_2 -timing, you can utilize the GPIO controlled SPI Slave Select option instead. -In this case, you should use GPIO based CS for all of your slaves and not just -the ones using mode 0 or 2 in order to guarantee correct CS toggling behavior. - -You can even use the same pin whose peripheral role is a SSEL, -but use it as a GPIO instead. diff --git a/Documentation/blackfin/gptimers-example.c b/Documentation/blackfin/gptimers-example.c deleted file mode 100644 index b1bd6340e74..00000000000 --- a/Documentation/blackfin/gptimers-example.c +++ /dev/null @@ -1,83 +0,0 @@ -/* - * Simple gptimers example - * http://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:drivers:gptimers - * - * Copyright 2007-2009 Analog Devices Inc. - * - * Licensed under the GPL-2 or later. - */ - -#include <linux/interrupt.h> -#include <linux/module.h> - -#include <asm/gptimers.h> -#include <asm/portmux.h> - -/* ... random driver includes ... */ - -#define DRIVER_NAME "gptimer_example" - -struct gptimer_data { - uint32_t period, width; -}; -static struct gptimer_data data; - -/* ... random driver state ... */ - -static irqreturn_t gptimer_example_irq(int irq, void *dev_id) -{ - struct gptimer_data *data = dev_id; - - /* make sure it was our timer which caused the interrupt */ - if (!get_gptimer_intr(TIMER5_id)) - return IRQ_NONE; - - /* read the width/period values that were captured for the waveform */ - data->width = get_gptimer_pwidth(TIMER5_id); - data->period = get_gptimer_period(TIMER5_id); - - /* acknowledge the interrupt */ - clear_gptimer_intr(TIMER5_id); - - /* tell the upper layers we took care of things */ - return IRQ_HANDLED; -} - -/* ... random driver code ... */ - -static int __init gptimer_example_init(void) -{ - int ret; - - /* grab the peripheral pins */ - ret = peripheral_request(P_TMR5, DRIVER_NAME); - if (ret) { - printk(KERN_NOTICE DRIVER_NAME ": peripheral request failed\n"); - return ret; - } - - /* grab the IRQ for the timer */ - ret = request_irq(IRQ_TIMER5, gptimer_example_irq, IRQF_SHARED, DRIVER_NAME, &data); - if (ret) { - printk(KERN_NOTICE DRIVER_NAME ": IRQ request failed\n"); - peripheral_free(P_TMR5); - return ret; - } - - /* setup the timer and enable it */ - set_gptimer_config(TIMER5_id, WDTH_CAP | PULSE_HI | PERIOD_CNT | IRQ_ENA); - enable_gptimers(TIMER5bit); - - return 0; -} -module_init(gptimer_example_init); - -static void __exit gptimer_example_exit(void) -{ - disable_gptimers(TIMER5bit); - free_irq(IRQ_TIMER5, &data); - peripheral_free(P_TMR5); -} -module_exit(gptimer_example_exit); - -MODULE_LICENSE("BSD"); |