diff options
author | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-22 11:22:59 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-22 11:22:59 -0700 |
commit | 7578634990fb47cc30083fbd812689aa6deacfc0 (patch) | |
tree | f493860658579d9572a19b3a41fcea2de035e49f /arch/arm/mach-sa1100/jornada720_ssp.c | |
parent | d7f5e3df3574c6e38b99f5fe22f15540b2b9811d (diff) | |
parent | 5957a4eb284dd6f522b248b674792416466555b2 (diff) |
Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (60 commits)
[ARM] 4524/1: S3C: Move register out of include/asm-arm/arch-s3c2410
[ARM] 4523/1: S3C: Remove FIFO_MAX from uncompression headers
[ARM] 4522/1: S3C: split include/asm-arm/arch/memory.h
[ARM] 4521/2: S3C: Reorganise VA mapping headers
[ARM] 4520/1: S3C: Remove old VA values from static map
[ARM] 4519/1: S3C: split S3C2400 values out of S3C24XX map.h
[ARM] 4518/1: S3C: Rename watchdog configuration options
[ARM] 4517/1: S3C: Fix debug macros for ARM926 output
[ARM] 4516/1: S3C: Fix uncompressor serial output for ARM926
[ARM] 4515/1: S3C: Move uncompress code to plat-s3c
[ARM] 4514/1: S3C: Rename DEBUG_S3C2410_PORT and DEBUG_S3C_UART
[ARM] 4513/1: S3C: Rename CONFIG_S3C2410_LOWLEVEL_UART_PORT
[ARM] 4512/1: S3C: rename the debug macros for per-cpu updates
[ARM] 4511/1: S3C: updated LLSERIAL Kconfig defines for CPU support
[ARM] 4510/1: S3C: split debug-macro support into plat-s3c
[ARM] 4509/1: S3C: Create initial arch/arm/plat-s3c
[ARM] 4508/1: S3C: Move items to include/asm-arm/plat-s3c
[ARM] 4461/1: MXC platform and i.MX31ADS core support
[ARM] 4507/1: pxa2xx clock_event_device
[ARM] 4497/1: Only allow safe cache configurations on ARMv6 and later
...
Diffstat (limited to 'arch/arm/mach-sa1100/jornada720_ssp.c')
-rw-r--r-- | arch/arm/mach-sa1100/jornada720_ssp.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/arch/arm/mach-sa1100/jornada720_ssp.c b/arch/arm/mach-sa1100/jornada720_ssp.c new file mode 100644 index 00000000000..0a45e1ac8ad --- /dev/null +++ b/arch/arm/mach-sa1100/jornada720_ssp.c @@ -0,0 +1,201 @@ +/** + * arch/arm/mac-sa1100/jornada720_ssp.c + * + * Copyright (C) 2006/2007 Kristoffer Ericson <Kristoffer.Ericson@gmail.com> + * Copyright (C) 2006 Filip Zyzniewski <filip.zyzniewski@tefnet.pl> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * SSP driver for the HP Jornada 710/720/728 + */ + +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#include <asm/hardware.h> +#include <asm/hardware/ssp.h> +#include <asm/arch/jornada720.h> + +static DEFINE_SPINLOCK(jornada_ssp_lock); +static unsigned long jornada_ssp_flags; + +/** + * jornada_ssp_reverse - reverses input byte + * + * we need to reverse all data we recieve from the mcu due to its physical location + * returns : 01110111 -> 11101110 + */ +u8 inline jornada_ssp_reverse(u8 byte) +{ + return + ((0x80 & byte) >> 7) | + ((0x40 & byte) >> 5) | + ((0x20 & byte) >> 3) | + ((0x10 & byte) >> 1) | + ((0x08 & byte) << 1) | + ((0x04 & byte) << 3) | + ((0x02 & byte) << 5) | + ((0x01 & byte) << 7); +}; +EXPORT_SYMBOL(jornada_ssp_reverse); + +/** + * jornada_ssp_byte - waits for ready ssp bus and sends byte + * + * waits for fifo buffer to clear and then transmits, if it doesn't then we will + * timeout after <timeout> rounds. Needs mcu running before its called. + * + * returns : %mcu output on success + * : %-ETIMEOUT on timeout + */ +int jornada_ssp_byte(u8 byte) +{ + int timeout = 400000; + u16 ret; + + while ((GPLR & GPIO_GPIO10)) { + if (!--timeout) { + printk(KERN_WARNING "SSP: timeout while waiting for transmit\n"); + return -ETIMEDOUT; + } + cpu_relax(); + } + + ret = jornada_ssp_reverse(byte) << 8; + + ssp_write_word(ret); + ssp_read_word(&ret); + + return jornada_ssp_reverse(ret); +}; +EXPORT_SYMBOL(jornada_ssp_byte); + +/** + * jornada_ssp_inout - decide if input is command or trading byte + * + * returns : (jornada_ssp_byte(byte)) on success + * : %-ETIMEOUT on timeout failure + */ +int jornada_ssp_inout(u8 byte) +{ + int ret, i; + + /* true means command byte */ + if (byte != TXDUMMY) { + ret = jornada_ssp_byte(byte); + /* Proper return to commands is TxDummy */ + if (ret != TXDUMMY) { + for (i = 0; i < 256; i++)/* flushing bus */ + if (jornada_ssp_byte(TXDUMMY) == -1) + break; + return -ETIMEDOUT; + } + } else /* Exchange TxDummy for data */ + ret = jornada_ssp_byte(TXDUMMY); + + return ret; +}; +EXPORT_SYMBOL(jornada_ssp_inout); + +/** + * jornada_ssp_start - enable mcu + * + */ +int jornada_ssp_start() +{ + spin_lock_irqsave(&jornada_ssp_lock, jornada_ssp_flags); + GPCR = GPIO_GPIO25; + udelay(50); + return 0; +}; +EXPORT_SYMBOL(jornada_ssp_start); + +/** + * jornada_ssp_end - disable mcu and turn off lock + * + */ +int jornada_ssp_end() +{ + GPSR = GPIO_GPIO25; + spin_unlock_irqrestore(&jornada_ssp_lock, jornada_ssp_flags); + return 0; +}; +EXPORT_SYMBOL(jornada_ssp_end); + +static int __init jornada_ssp_probe(struct platform_device *dev) +{ + int ret; + + GPSR = GPIO_GPIO25; + + ret = ssp_init(); + + /* worked fine, lets not bother with anything else */ + if (!ret) { + printk(KERN_INFO "SSP: device initialized with irq\n"); + return ret; + } + + printk(KERN_WARNING "SSP: initialization failed, trying non-irq solution \n"); + + /* init of Serial 4 port */ + Ser4MCCR0 = 0; + Ser4SSCR0 = 0x0387; + Ser4SSCR1 = 0x18; + + /* clear out any left over data */ + ssp_flush(); + + /* enable MCU */ + jornada_ssp_start(); + + /* see if return value makes sense */ + ret = jornada_ssp_inout(GETBRIGHTNESS); + + /* seems like it worked, just feed it with TxDummy to get rid of data */ + if (ret == TxDummy) + jornada_ssp_inout(TXDUMMY); + + jornada_ssp_end(); + + /* failed, lets just kill everything */ + if (ret == -ETIMEDOUT) { + printk(KERN_WARNING "SSP: attempts failed, bailing\n"); + ssp_exit(); + return -ENODEV; + } + + /* all fine */ + printk(KERN_INFO "SSP: device initialized\n"); + return 0; +}; + +static int jornada_ssp_remove(struct platform_device *dev) +{ + /* Note that this doesnt actually remove the driver, since theres nothing to remove + * It just makes sure everything is turned off */ + GPSR = GPIO_GPIO25; + ssp_exit(); + return 0; +}; + +struct platform_driver jornadassp_driver = { + .probe = jornada_ssp_probe, + .remove = jornada_ssp_remove, + .driver = { + .name = "jornada_ssp", + }, +}; + +static int __init jornada_ssp_init(void) +{ + return platform_driver_register(&jornadassp_driver); +} |