diff options
Diffstat (limited to 'drivers/sbus/char/vfc_i2c.c')
| -rw-r--r-- | drivers/sbus/char/vfc_i2c.c | 335 |
1 files changed, 0 insertions, 335 deletions
diff --git a/drivers/sbus/char/vfc_i2c.c b/drivers/sbus/char/vfc_i2c.c deleted file mode 100644 index 32b986e..0000000 --- a/drivers/sbus/char/vfc_i2c.c +++ /dev/null @@ -1,335 +0,0 @@ -/* - * drivers/sbus/char/vfc_i2c.c - * - * Driver for the Videopix Frame Grabber. - * - * Functions that support the Phillips i2c(I squared C) bus on the vfc - * Documentation for the Phillips I2C bus can be found on the - * phillips home page - * - * Copyright (C) 1996 Manish Vachharajani (mvachhar@noc.rutgers.edu) - * - */ - -/* NOTE: It seems to me that the documentation regarding the -pcd8584t/pcf8584 does not show the correct way to address the i2c bus. -Based on the information on the I2C bus itself and the remainder of -the Phillips docs the following algorithms appear to be correct. I am -fairly certain that the flowcharts in the phillips docs are wrong. */ - - -#include <linux/kernel.h> -#include <linux/string.h> -#include <linux/slab.h> -#include <linux/errno.h> -#include <linux/sched.h> -#include <linux/wait.h> -#include <linux/delay.h> -#include <asm/openprom.h> -#include <asm/oplib.h> -#include <asm/io.h> -#include <asm/system.h> -#include <asm/sbus.h> - -#if 0 -#define VFC_I2C_DEBUG -#endif - -#include "vfc.h" -#include "vfc_i2c.h" - -#define WRITE_S1(__val) \ - sbus_writel(__val, &dev->regs->i2c_s1) -#define WRITE_REG(__val) \ - sbus_writel(__val, &dev->regs->i2c_reg) - -#define VFC_I2C_READ (0x1) -#define VFC_I2C_WRITE (0x0) - -/****** - The i2c bus controller chip on the VFC is a pcd8584t, but - phillips claims it doesn't exist. As far as I can tell it is - identical to the PCF8584 so I treat it like it is the pcf8584. - - NOTE: The pcf8584 only cares - about the msb of the word you feed it -*****/ - -int vfc_pcf8584_init(struct vfc_dev *dev) -{ - /* This will also choose register S0_OWN so we can set it. */ - WRITE_S1(RESET); - - /* The pcf8584 shifts this value left one bit and uses - * it as its i2c bus address. - */ - WRITE_REG(0x55000000); - - /* This will set the i2c bus at the same speed sun uses, - * and set another magic bit. - */ - WRITE_S1(SELECT(S2)); - WRITE_REG(0x14000000); - - /* Enable the serial port, idle the i2c bus and set - * the data reg to s0. - */ - WRITE_S1(CLEAR_I2C_BUS); - udelay(100); - return 0; -} - -void vfc_i2c_delay_no_busy(struct vfc_dev *dev, unsigned long usecs) -{ - schedule_timeout_uninterruptible(usecs_to_jiffies(usecs)); -} - -void inline vfc_i2c_delay(struct vfc_dev *dev) -{ - vfc_i2c_delay_no_busy(dev, 100); -} - -int vfc_init_i2c_bus(struct vfc_dev *dev) -{ - WRITE_S1(ENABLE_SERIAL | SELECT(S0) | ACK); - vfc_i2c_reset_bus(dev); - return 0; -} - -int vfc_i2c_reset_bus(struct vfc_dev *dev) -{ - VFC_I2C_DEBUG_PRINTK((KERN_DEBUG "vfc%d: Resetting the i2c bus\n", - dev->instance)); - if(dev == NULL) - return -EINVAL; - if(dev->regs == NULL) - return -EINVAL; - WRITE_S1(SEND_I2C_STOP); - WRITE_S1(SEND_I2C_STOP | ACK); - vfc_i2c_delay(dev); - WRITE_S1(CLEAR_I2C_BUS); - VFC_I2C_DEBUG_PRINTK((KERN_DEBUG "vfc%d: I2C status %x\n", - dev->instance, - sbus_readl(&dev->regs->i2c_s1))); - return 0; -} - -static int vfc_i2c_wait_for_bus(struct vfc_dev *dev) -{ - int timeout = 1000; - - while(!(sbus_readl(&dev->regs->i2c_s1) & BB)) { - if(!(timeout--)) - return -ETIMEDOUT; - vfc_i2c_delay(dev); - } - return 0; -} - -static int vfc_i2c_wait_for_pin(struct vfc_dev *dev, int ack) -{ - int timeout = 1000; - int s1; - - while ((s1 = sbus_readl(&dev->regs->i2c_s1)) & PIN) { - if (!(timeout--)) - return -ETIMEDOUT; - vfc_i2c_delay(dev); - } - if (ack == VFC_I2C_ACK_CHECK) { - if(s1 & LRB) - return -EIO; - } - return 0; -} - -#define SHIFT(a) ((a) << 24) -static int vfc_i2c_xmit_addr(struct vfc_dev *dev, unsigned char addr, - char mode) -{ - int ret, raddr; -#if 1 - WRITE_S1(SEND_I2C_STOP | ACK); - WRITE_S1(SELECT(S0) | ENABLE_SERIAL); - vfc_i2c_delay(dev); -#endif - - switch(mode) { - case VFC_I2C_READ: - raddr = SHIFT(((unsigned int)addr | 0x1)); - WRITE_REG(raddr); - VFC_I2C_DEBUG_PRINTK(("vfc%d: receiving from i2c addr 0x%x\n", - dev->instance, addr | 0x1)); - break; - case VFC_I2C_WRITE: - raddr = SHIFT((unsigned int)addr & ~0x1); - WRITE_REG(raddr); - VFC_I2C_DEBUG_PRINTK(("vfc%d: sending to i2c addr 0x%x\n", - dev->instance, addr & ~0x1)); - break; - default: - return -EINVAL; - }; - - WRITE_S1(SEND_I2C_START); - vfc_i2c_delay(dev); - ret = vfc_i2c_wait_for_pin(dev,VFC_I2C_ACK_CHECK); /* We wait - for the - i2c send - to finish - here but - Sun - doesn't, - hmm */ - if (ret) { - printk(KERN_ERR "vfc%d: VFC xmit addr timed out or no ack\n", - dev->instance); - return ret; - } else if (mode == VFC_I2C_READ) { - if ((ret = sbus_readl(&dev->regs->i2c_reg) & 0xff000000) != raddr) { - printk(KERN_WARNING - "vfc%d: returned slave address " - "mismatch(%x,%x)\n", - dev->instance, raddr, ret); - } - } - return 0; -} - -static int vfc_i2c_xmit_byte(struct vfc_dev *dev,unsigned char *byte) -{ - int ret; - u32 val = SHIFT((unsigned int)*byte); - - WRITE_REG(val); - - ret = vfc_i2c_wait_for_pin(dev, VFC_I2C_ACK_CHECK); - switch(ret) { - case -ETIMEDOUT: - printk(KERN_ERR "vfc%d: VFC xmit byte timed out or no ack\n", - dev->instance); - break; - case -EIO: - ret = XMIT_LAST_BYTE; - break; - default: - break; - }; - - return ret; -} - -static int vfc_i2c_recv_byte(struct vfc_dev *dev, unsigned char *byte, - int last) -{ - int ret; - - if (last) { - WRITE_REG(NEGATIVE_ACK); - VFC_I2C_DEBUG_PRINTK(("vfc%d: sending negative ack\n", - dev->instance)); - } else { - WRITE_S1(ACK); - } - - ret = vfc_i2c_wait_for_pin(dev, VFC_I2C_NO_ACK_CHECK); - if(ret) { - printk(KERN_ERR "vfc%d: " - "VFC recv byte timed out\n", - dev->instance); - } - *byte = (sbus_readl(&dev->regs->i2c_reg)) >> 24; - return ret; -} - -int vfc_i2c_recvbuf(struct vfc_dev *dev, unsigned char addr, - char *buf, int count) -{ - int ret, last; - - if(!(count && buf && dev && dev->regs) ) - return -EINVAL; - - if ((ret = vfc_i2c_wait_for_bus(dev))) { - printk(KERN_ERR "vfc%d: VFC I2C bus busy\n", dev->instance); - return ret; - } - - if ((ret = vfc_i2c_xmit_addr(dev, addr, VFC_I2C_READ))) { - WRITE_S1(SEND_I2C_STOP); - vfc_i2c_delay(dev); - return ret; - } - - last = 0; - while (count--) { - if (!count) - last = 1; - if ((ret = vfc_i2c_recv_byte(dev, buf, last))) { - printk(KERN_ERR "vfc%d: " - "VFC error while receiving byte\n", - dev->instance); - WRITE_S1(SEND_I2C_STOP); - ret = -EINVAL; - } - buf++; - } - WRITE_S1(SEND_I2C_STOP | ACK); - vfc_i2c_delay(dev); - return ret; -} - -int vfc_i2c_sendbuf(struct vfc_dev *dev, unsigned char addr, - char *buf, int count) -{ - int ret; - - if (!(buf && dev && dev->regs)) - return -EINVAL; - - if ((ret = vfc_i2c_wait_for_bus(dev))) { - printk(KERN_ERR "vfc%d: VFC I2C bus busy\n", dev->instance); - return ret; - } - - if ((ret = vfc_i2c_xmit_addr(dev, addr, VFC_I2C_WRITE))) { - WRITE_S1(SEND_I2C_STOP); - vfc_i2c_delay(dev); - return ret; - } - - while(count--) { - ret = vfc_i2c_xmit_byte(dev, buf); - switch(ret) { - case XMIT_LAST_BYTE: - VFC_I2C_DEBUG_PRINTK(("vfc%d: " - "Receiver ended transmission with " - " %d bytes remaining\n", - dev->instance, count)); - ret = 0; - goto done; - break; - case 0: - break; - default: - printk(KERN_ERR "vfc%d: " - "VFC error while sending byte\n", dev->instance); - break; - }; - - buf++; - } -done: - WRITE_S1(SEND_I2C_STOP | ACK); - vfc_i2c_delay(dev); - return ret; -} - - - - - - - - - |
