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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-22 11:22:59 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-22 11:22:59 -0700
commit7578634990fb47cc30083fbd812689aa6deacfc0 (patch)
treef493860658579d9572a19b3a41fcea2de035e49f /arch/arm/mach-sa1100/jornada720_ssp.c
parentd7f5e3df3574c6e38b99f5fe22f15540b2b9811d (diff)
parent5957a4eb284dd6f522b248b674792416466555b2 (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.c201
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);
+}