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@@ -1,467 +0,0 @@
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-/*
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- * Microcontroller Message Bus
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- *
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- * Copyright (c) 2009 Michael Buesch <[email protected]>
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- *
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- * Licensed under the GNU/GPL. See COPYING for details.
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- */
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-
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-#include "ucmb.h"
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-
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-#include <linux/module.h>
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-#include <linux/platform_device.h>
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-#include <linux/miscdevice.h>
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-#include <linux/fs.h>
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-#include <linux/spi/spi.h>
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-#include <linux/spi/spi_gpio.h>
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-#include <linux/spi/spi_bitbang.h>
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-#include <linux/gfp.h>
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-#include <linux/delay.h>
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-#include <linux/crc16.h>
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-
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-
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-#define PFX "ucmb: "
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-
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-#define DEBUG
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-
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-
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-MODULE_LICENSE("GPL");
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-MODULE_DESCRIPTION("Microcontroller Message Bus");
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-MODULE_AUTHOR("Michael Buesch");
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-
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-
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-struct ucmb {
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- unsigned int msg_delay_ms;
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-
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- /* Misc character device driver */
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- struct miscdevice mdev;
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- struct file_operations mdev_fops;
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-
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- /* SPI driver */
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- struct spi_device *sdev;
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-
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- /* SPI-GPIO driver */
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- struct spi_gpio_platform_data spi_gpio_pdata;
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- struct platform_device spi_gpio_pdev;
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-};
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-
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-struct ucmb_message_hdr {
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- __le16 magic; /* UCMB_MAGIC */
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- __le16 len; /* Payload length (excluding header) */
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-} __attribute__((packed));
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-
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-struct ucmb_message_footer {
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- __le16 crc; /* CRC of the header + payload. */
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-} __attribute__((packed));
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-
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-struct ucmb_status {
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- __le16 magic; /* UCMB_MAGIC */
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- __le16 code; /* enum ucmb_status_code */
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-} __attribute__((packed));
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-
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-#define UCMB_MAGIC 0x1337
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-#define UCMB_MAX_MSG_LEN 0x200
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-
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-enum ucmb_status_code {
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- UCMB_STAT_OK = 0,
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- UCMB_STAT_EPROTO, /* Protocol format error */
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- UCMB_STAT_ENOMEM, /* Out of memory */
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- UCMB_STAT_E2BIG, /* Message too big */
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- UCMB_STAT_ECRC, /* CRC error */
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-};
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-
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-
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-static int ucmb_spi_busnum_count = 1337;
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-
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-
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-static struct ucmb_platform_data ucmb_list[] = {
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- { //FIXME don't define it here.
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- .name = "ucmb",
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- .gpio_cs = 3,
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- .gpio_sck = 0,
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- .gpio_miso = 1,
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- .gpio_mosi = 2,
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- .mode = SPI_MODE_0,
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- .max_speed_hz = 128000, /* Hz */
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- .msg_delay_ms = 1, /* mS */
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- },
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-};
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-
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-
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-static int __devinit ucmb_spi_probe(struct spi_device *sdev)
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-{
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- return 0;
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-}
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-
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-static int __devexit ucmb_spi_remove(struct spi_device *sdev)
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-{
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- return 0;
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-}
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-
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-static struct spi_driver ucmb_spi_driver = {
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- .driver = {
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- .name = "ucmb",
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- .bus = &spi_bus_type,
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- .owner = THIS_MODULE,
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- },
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- .probe = ucmb_spi_probe,
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- .remove = __devexit_p(ucmb_spi_remove),
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-};
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-
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-static int ucmb_status_code_to_errno(enum ucmb_status_code code)
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-{
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- switch (code) {
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- case UCMB_STAT_OK:
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- return 0;
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- case UCMB_STAT_EPROTO:
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- return -EPROTO;
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- case UCMB_STAT_ENOMEM:
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- return -ENOMEM;
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- case UCMB_STAT_E2BIG:
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- return -E2BIG;
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- case UCMB_STAT_ECRC:
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- return -EBADMSG;
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- }
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- return -EBUSY;
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-}
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-
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-static inline struct ucmb * filp_to_ucmb(struct file *filp)
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-{
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- return container_of(filp->f_op, struct ucmb, mdev_fops);
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-}
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-
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-static ssize_t ucmb_read(struct file *filp, char __user *user_buf,
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- size_t size, loff_t *offp)
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-{
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- struct ucmb *ucmb = filp_to_ucmb(filp);
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- u8 *buf;
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- int res, err;
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- struct ucmb_message_hdr hdr;
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- struct ucmb_message_footer footer;
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- struct ucmb_status status = { .magic = cpu_to_le16(UCMB_MAGIC), };
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- u16 crc = 0xFFFF;
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-
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- size = min_t(size_t, size, PAGE_SIZE);
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-
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- err = -ENOMEM;
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- buf = (char *)__get_free_page(GFP_KERNEL);
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- if (!buf)
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- goto out;
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-
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- err = spi_read(ucmb->sdev, (u8 *)&hdr, sizeof(hdr));
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- if (err)
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- goto out_free;
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-#ifdef DEBUG
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- printk(KERN_DEBUG PFX "Received message header 0x%04X 0x%04X\n",
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- le16_to_cpu(hdr.magic), le16_to_cpu(hdr.len));
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-#endif
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- err = -EPROTO;
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- if (hdr.magic != cpu_to_le16(UCMB_MAGIC))
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- goto out_free;
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- err = -ENOBUFS;
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- if (size < le16_to_cpu(hdr.len))
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- goto out_free;
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- size = le16_to_cpu(hdr.len);
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- err = spi_read(ucmb->sdev, buf, size);
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- if (err)
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- goto out_free;
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- err = spi_read(ucmb->sdev, (u8 *)&footer, sizeof(footer));
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- if (err)
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- goto out_free;
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-
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- crc = crc16(crc, &hdr, sizeof(hdr));
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- crc = crc16(crc, buf, size);
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- crc ^= 0xFFFF;
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- if (crc != le16_to_cpu(footer.crc)) {
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- err = -EPROTO;
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- status.code = UCMB_STAT_ECRC;
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- goto out_send_status;
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- }
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-
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- if (copy_to_user(user_buf, buf, size)) {
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- err = -EFAULT;
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- status.code = UCMB_STAT_ENOMEM;
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- goto out_send_status;
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- }
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-
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- status.code = UCMB_STAT_OK;
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- err = 0;
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-
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-out_send_status:
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- res = spi_write(ucmb->sdev, (u8 *)&status, sizeof(status));
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- if (res && !err)
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- err = res;
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-out_free:
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- free_page((unsigned long)buf);
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-out:
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- return err ? err : size;
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-}
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-
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-static ssize_t ucmb_write(struct file *filp, const char __user *user_buf,
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- size_t size, loff_t *offp)
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-{
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- struct ucmb *ucmb = filp_to_ucmb(filp);
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- u8 *buf;
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- int err;
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- struct ucmb_message_hdr hdr = { .magic = cpu_to_le16(UCMB_MAGIC), };
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- struct ucmb_message_footer footer = { .crc = 0xFFFF, };
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- struct ucmb_status status;
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- struct spi_transfer spi_hdr_xfer;
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- struct spi_transfer spi_footer_xfer;
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- struct spi_transfer spi_data_xfer;
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- struct spi_message spi_msg;
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-
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- err = -ENOMEM;
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- buf = (char *)__get_free_page(GFP_KERNEL);
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- if (!buf)
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- goto out;
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-
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- size = min_t(size_t, PAGE_SIZE, size);
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- size = min_t(size_t, UCMB_MAX_MSG_LEN, size);
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- err = -EFAULT;
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- if (copy_from_user(buf, user_buf, size))
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- goto out_free;
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- hdr.len = cpu_to_le16(size);
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-
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- footer.crc = crc16(footer.crc, &hdr, sizeof(hdr));
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- footer.crc = crc16(footer.crc, buf, size);
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- footer.crc ^= 0xFFFF;
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-
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- spi_message_init(&spi_msg);
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-
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- memset(&spi_hdr_xfer, 0, sizeof(spi_hdr_xfer));
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- spi_hdr_xfer.tx_buf = &hdr;
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- spi_hdr_xfer.len = sizeof(hdr);
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- spi_message_add_tail(&spi_hdr_xfer, &spi_msg);
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-
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- memset(&spi_data_xfer, 0, sizeof(spi_data_xfer));
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- spi_data_xfer.tx_buf = buf;
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- spi_data_xfer.len = size;
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- spi_message_add_tail(&spi_data_xfer, &spi_msg);
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-
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- memset(&spi_footer_xfer, 0, sizeof(spi_footer_xfer));
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- spi_footer_xfer.tx_buf = &footer;
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- spi_footer_xfer.len = sizeof(footer);
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- spi_message_add_tail(&spi_footer_xfer, &spi_msg);
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-
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- /* Send the message, including header. */
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- err = spi_sync(ucmb->sdev, &spi_msg);
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- if (err)
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- goto out_free;
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-
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- /* The microcontroller deserves some time to process the message. */
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- if (ucmb->msg_delay_ms)
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- msleep(ucmb->msg_delay_ms);
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-
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- /* Get the status code. */
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- err = spi_read(ucmb->sdev, (u8 *)&status, sizeof(status));
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- if (err)
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- goto out_free;
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-#ifdef DEBUG
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- printk(KERN_DEBUG PFX "Sent message. Status report: 0x%04X 0x%04X\n",
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- le16_to_cpu(status.magic), le16_to_cpu(status.code));
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-#endif
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- err = -EPROTO;
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- if (status.magic != cpu_to_le16(UCMB_MAGIC))
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- goto out_free;
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- err = ucmb_status_code_to_errno(le16_to_cpu(status.code));
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- if (err)
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- goto out_free;
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-
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-out_free:
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- free_page((unsigned long)buf);
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-out:
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- return err ? err : size;
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-}
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-
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-static int __devinit ucmb_probe(struct platform_device *pdev)
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-{
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- struct ucmb_platform_data *pdata;
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- struct ucmb *ucmb;
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- int err;
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- const int bus_num = ucmb_spi_busnum_count++;
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- struct spi_bitbang *bb;
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-
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- pdata = pdev->dev.platform_data;
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- if (!pdata)
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- return -ENXIO;
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-
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- ucmb = kzalloc(sizeof(struct ucmb), GFP_KERNEL);
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- if (!ucmb)
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- return -ENOMEM;
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- ucmb->msg_delay_ms = pdata->msg_delay_ms;
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-
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- /* Create the SPI GPIO bus master. */
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-
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-#ifdef CONFIG_SPI_GPIO_MODULE
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- err = request_module("spi_gpio");
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- if (err)
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- printk(KERN_WARNING PFX "Failed to request spi_gpio module\n");
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-#endif /* CONFIG_SPI_GPIO_MODULE */
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-
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- ucmb->spi_gpio_pdata.sck = pdata->gpio_sck;
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- ucmb->spi_gpio_pdata.mosi = pdata->gpio_mosi;
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- ucmb->spi_gpio_pdata.miso = pdata->gpio_miso;
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- ucmb->spi_gpio_pdata.num_chipselect = 1;
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-
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- ucmb->spi_gpio_pdev.name = "spi_gpio";
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- ucmb->spi_gpio_pdev.id = bus_num;
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- ucmb->spi_gpio_pdev.dev.platform_data = &ucmb->spi_gpio_pdata;
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-
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- err = platform_device_register(&ucmb->spi_gpio_pdev);
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- if (err) {
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- printk(KERN_ERR PFX "Failed to register SPI-GPIO platform device\n");
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- goto err_free_ucmb;
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- }
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- bb = platform_get_drvdata(&ucmb->spi_gpio_pdev);
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- if (!bb || !bb->master) {
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- printk(KERN_ERR PFX "No bitbanged master device found.\n");
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- goto err_unreg_spi_gpio_pdev;
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- }
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-
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- /* Create the SPI device. */
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-
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- ucmb->sdev = spi_alloc_device(bb->master);
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- if (!ucmb->sdev) {
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- printk(KERN_ERR PFX "Failed to allocate SPI device\n");
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- goto err_unreg_spi_gpio_pdev;
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- }
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- ucmb->sdev->max_speed_hz = pdata->max_speed_hz;
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- ucmb->sdev->chip_select = 0;
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- ucmb->sdev->mode = pdata->mode;
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- strlcpy(ucmb->sdev->modalias, "ucmb", /* We are the SPI driver. */
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- sizeof(ucmb->sdev->modalias));
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- ucmb->sdev->controller_data = (void *)pdata->gpio_cs;
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- err = spi_add_device(ucmb->sdev);
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- if (err) {
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- printk(KERN_ERR PFX "Failed to add SPI device\n");
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- goto err_free_spi_device;
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- }
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-
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- /* Create the Misc char device. */
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-
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- ucmb->mdev.minor = MISC_DYNAMIC_MINOR;
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- ucmb->mdev.name = pdata->name;
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- ucmb->mdev.parent = &pdev->dev;
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- ucmb->mdev_fops.read = ucmb_read;
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- ucmb->mdev_fops.write = ucmb_write;
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- ucmb->mdev.fops = &ucmb->mdev_fops;
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-
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- err = misc_register(&ucmb->mdev);
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- if (err) {
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- printk(KERN_ERR PFX "Failed to register miscdev %s\n",
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- ucmb->mdev.name);
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- goto err_unreg_spi_device;
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- }
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-
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- platform_set_drvdata(pdev, ucmb);
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-
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- printk(KERN_INFO PFX "Registered message bus \"%s\"\n", pdata->name);
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-
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- return 0;
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-
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-err_unreg_spi_device:
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- spi_unregister_device(ucmb->sdev);
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-err_free_spi_device:
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- spi_dev_put(ucmb->sdev);
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-err_unreg_spi_gpio_pdev:
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- platform_device_unregister(&ucmb->spi_gpio_pdev);
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-err_free_ucmb:
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- kfree(ucmb);
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-
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- return err;
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-}
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-
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-static int __devexit ucmb_remove(struct platform_device *pdev)
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-{
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- struct ucmb *ucmb = platform_get_drvdata(pdev);
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- int err;
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-
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- err = misc_deregister(&ucmb->mdev);
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- if (err) {
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- printk(KERN_ERR PFX "Failed to unregister miscdev %s\n",
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- ucmb->mdev.name);
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- }
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- spi_unregister_device(ucmb->sdev);
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- spi_dev_put(ucmb->sdev);
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- platform_device_unregister(&ucmb->spi_gpio_pdev);
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-
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- kfree(ucmb);
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- platform_set_drvdata(pdev, NULL);
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-
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- return 0;
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-}
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-
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-static struct platform_driver ucmb_driver = {
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- .driver = {
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- .name = "ucmb",
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- .owner = THIS_MODULE,
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|
- },
|
|
|
- .probe = ucmb_probe,
|
|
|
- .remove = __devexit_p(ucmb_probe),
|
|
|
-};
|
|
|
-
|
|
|
-static int ucmb_modinit(void)
|
|
|
-{
|
|
|
- struct ucmb_platform_data *pdata;
|
|
|
- struct platform_device *pdev;
|
|
|
- int err, i;
|
|
|
-
|
|
|
- printk(KERN_INFO "Microcontroller message bus driver\n");
|
|
|
-
|
|
|
- err = platform_driver_register(&ucmb_driver);
|
|
|
- if (err) {
|
|
|
- printk(KERN_ERR PFX "Failed to register platform driver\n");
|
|
|
- return err;
|
|
|
- }
|
|
|
- err = spi_register_driver(&ucmb_spi_driver);
|
|
|
- if (err) {
|
|
|
- printk(KERN_ERR PFX "Failed to register SPI driver\n");
|
|
|
- platform_driver_unregister(&ucmb_driver);
|
|
|
- return err;
|
|
|
- }
|
|
|
-
|
|
|
- for (i = 0; i < ARRAY_SIZE(ucmb_list); i++) {
|
|
|
- pdata = &ucmb_list[i];
|
|
|
-
|
|
|
- pdev = platform_device_alloc("ucmb", i);
|
|
|
- if (!pdev) {
|
|
|
- printk(KERN_ERR PFX "Failed to allocate platform device.\n");
|
|
|
- break;
|
|
|
- }
|
|
|
- err = platform_device_add_data(pdev, pdata, sizeof(*pdata));
|
|
|
- if (err) {
|
|
|
- printk(KERN_ERR PFX "Failed to add platform data.\n");
|
|
|
- platform_device_put(pdev);
|
|
|
- break;
|
|
|
- }
|
|
|
- err = platform_device_add(pdev);
|
|
|
- if (err) {
|
|
|
- printk(KERN_ERR PFX "Failed to register platform device.\n");
|
|
|
- platform_device_put(pdev);
|
|
|
- break;
|
|
|
- }
|
|
|
- pdata->pdev = pdev;
|
|
|
- }
|
|
|
-
|
|
|
- return 0;
|
|
|
-}
|
|
|
-module_init(ucmb_modinit);
|
|
|
-
|
|
|
-static void ucmb_modexit(void)
|
|
|
-{
|
|
|
- struct ucmb_platform_data *pdata;
|
|
|
- int i;
|
|
|
-
|
|
|
- for (i = 0; i < ARRAY_SIZE(ucmb_list); i++) {
|
|
|
- pdata = &ucmb_list[i];
|
|
|
-
|
|
|
- if (pdata->pdev) {
|
|
|
- platform_device_unregister(pdata->pdev);
|
|
|
- platform_device_put(pdata->pdev);
|
|
|
- }
|
|
|
- }
|
|
|
- spi_unregister_driver(&ucmb_spi_driver);
|
|
|
- platform_driver_unregister(&ucmb_driver);
|
|
|
-}
|
|
|
-module_exit(ucmb_modexit);
|