777 lines
17 KiB
C
777 lines
17 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* FSI-attached I2C master algorithm
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*
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* Copyright 2018 IBM Corporation
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/bitfield.h>
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#include <linux/bitops.h>
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#include <linux/delay.h>
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#include <linux/device.h>
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#include <linux/errno.h>
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#include <linux/fsi.h>
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#include <linux/i2c.h>
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#include <linux/jiffies.h>
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#include <linux/kernel.h>
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#include <linux/list.h>
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#include <linux/module.h>
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#include <linux/mutex.h>
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#include <linux/of.h>
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#include <linux/slab.h>
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#define FSI_ENGID_I2C 0x7
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#define I2C_DEFAULT_CLK_DIV 6
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/* i2c registers */
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#define I2C_FSI_FIFO 0x00
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#define I2C_FSI_CMD 0x04
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#define I2C_FSI_MODE 0x08
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#define I2C_FSI_WATER_MARK 0x0C
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#define I2C_FSI_INT_MASK 0x10
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#define I2C_FSI_INT_COND 0x14
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#define I2C_FSI_OR_INT_MASK 0x14
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#define I2C_FSI_INTS 0x18
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#define I2C_FSI_AND_INT_MASK 0x18
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#define I2C_FSI_STAT 0x1C
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#define I2C_FSI_RESET_I2C 0x1C
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#define I2C_FSI_ESTAT 0x20
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#define I2C_FSI_RESET_ERR 0x20
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#define I2C_FSI_RESID_LEN 0x24
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#define I2C_FSI_SET_SCL 0x24
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#define I2C_FSI_PORT_BUSY 0x28
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#define I2C_FSI_RESET_SCL 0x2C
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#define I2C_FSI_SET_SDA 0x30
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#define I2C_FSI_RESET_SDA 0x34
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/* cmd register */
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#define I2C_CMD_WITH_START BIT(31)
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#define I2C_CMD_WITH_ADDR BIT(30)
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#define I2C_CMD_RD_CONT BIT(29)
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#define I2C_CMD_WITH_STOP BIT(28)
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#define I2C_CMD_FORCELAUNCH BIT(27)
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#define I2C_CMD_ADDR GENMASK(23, 17)
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#define I2C_CMD_READ BIT(16)
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#define I2C_CMD_LEN GENMASK(15, 0)
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/* mode register */
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#define I2C_MODE_CLKDIV GENMASK(31, 16)
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#define I2C_MODE_PORT GENMASK(15, 10)
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#define I2C_MODE_ENHANCED BIT(3)
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#define I2C_MODE_DIAG BIT(2)
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#define I2C_MODE_PACE_ALLOW BIT(1)
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#define I2C_MODE_WRAP BIT(0)
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/* watermark register */
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#define I2C_WATERMARK_HI GENMASK(15, 12)
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#define I2C_WATERMARK_LO GENMASK(7, 4)
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#define I2C_FIFO_HI_LVL 4
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#define I2C_FIFO_LO_LVL 4
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/* interrupt register */
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#define I2C_INT_INV_CMD BIT(15)
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#define I2C_INT_PARITY BIT(14)
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#define I2C_INT_BE_OVERRUN BIT(13)
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#define I2C_INT_BE_ACCESS BIT(12)
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#define I2C_INT_LOST_ARB BIT(11)
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#define I2C_INT_NACK BIT(10)
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#define I2C_INT_DAT_REQ BIT(9)
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#define I2C_INT_CMD_COMP BIT(8)
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#define I2C_INT_STOP_ERR BIT(7)
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#define I2C_INT_BUSY BIT(6)
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#define I2C_INT_IDLE BIT(5)
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/* status register */
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#define I2C_STAT_INV_CMD BIT(31)
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#define I2C_STAT_PARITY BIT(30)
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#define I2C_STAT_BE_OVERRUN BIT(29)
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#define I2C_STAT_BE_ACCESS BIT(28)
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#define I2C_STAT_LOST_ARB BIT(27)
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#define I2C_STAT_NACK BIT(26)
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#define I2C_STAT_DAT_REQ BIT(25)
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#define I2C_STAT_CMD_COMP BIT(24)
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#define I2C_STAT_STOP_ERR BIT(23)
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#define I2C_STAT_MAX_PORT GENMASK(19, 16)
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#define I2C_STAT_ANY_INT BIT(15)
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#define I2C_STAT_SCL_IN BIT(11)
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#define I2C_STAT_SDA_IN BIT(10)
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#define I2C_STAT_PORT_BUSY BIT(9)
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#define I2C_STAT_SELF_BUSY BIT(8)
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#define I2C_STAT_FIFO_COUNT GENMASK(7, 0)
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#define I2C_STAT_ERR (I2C_STAT_INV_CMD | \
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I2C_STAT_PARITY | \
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I2C_STAT_BE_OVERRUN | \
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I2C_STAT_BE_ACCESS | \
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I2C_STAT_LOST_ARB | \
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I2C_STAT_NACK | \
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I2C_STAT_STOP_ERR)
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#define I2C_STAT_ANY_RESP (I2C_STAT_ERR | \
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I2C_STAT_DAT_REQ | \
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I2C_STAT_CMD_COMP)
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/* extended status register */
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#define I2C_ESTAT_FIFO_SZ GENMASK(31, 24)
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#define I2C_ESTAT_SCL_IN_SY BIT(15)
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#define I2C_ESTAT_SDA_IN_SY BIT(14)
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#define I2C_ESTAT_S_SCL BIT(13)
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#define I2C_ESTAT_S_SDA BIT(12)
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#define I2C_ESTAT_M_SCL BIT(11)
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#define I2C_ESTAT_M_SDA BIT(10)
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#define I2C_ESTAT_HI_WATER BIT(9)
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#define I2C_ESTAT_LO_WATER BIT(8)
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#define I2C_ESTAT_PORT_BUSY BIT(7)
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#define I2C_ESTAT_SELF_BUSY BIT(6)
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#define I2C_ESTAT_VERSION GENMASK(4, 0)
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/* port busy register */
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#define I2C_PORT_BUSY_RESET BIT(31)
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/* wait for command complete or data request */
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#define I2C_CMD_SLEEP_MAX_US 500
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#define I2C_CMD_SLEEP_MIN_US 50
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/* wait after reset; choose time from legacy driver */
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#define I2C_RESET_SLEEP_MAX_US 2000
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#define I2C_RESET_SLEEP_MIN_US 1000
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/* choose timeout length from legacy driver; it's well tested */
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#define I2C_ABORT_TIMEOUT msecs_to_jiffies(100)
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struct fsi_i2c_master {
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struct fsi_device *fsi;
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u8 fifo_size;
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struct list_head ports;
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struct mutex lock;
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};
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struct fsi_i2c_port {
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struct list_head list;
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struct i2c_adapter adapter;
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struct fsi_i2c_master *master;
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u16 port;
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u16 xfrd;
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};
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static int fsi_i2c_read_reg(struct fsi_device *fsi, unsigned int reg,
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u32 *data)
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{
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int rc;
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__be32 data_be;
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rc = fsi_device_read(fsi, reg, &data_be, sizeof(data_be));
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if (rc)
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return rc;
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*data = be32_to_cpu(data_be);
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return 0;
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}
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static int fsi_i2c_write_reg(struct fsi_device *fsi, unsigned int reg,
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u32 *data)
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{
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__be32 data_be = cpu_to_be32p(data);
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return fsi_device_write(fsi, reg, &data_be, sizeof(data_be));
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}
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static int fsi_i2c_dev_init(struct fsi_i2c_master *i2c)
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{
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int rc;
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u32 mode = I2C_MODE_ENHANCED, extended_status, watermark;
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u32 interrupt = 0;
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/* since we use polling, disable interrupts */
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_INT_MASK, &interrupt);
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if (rc)
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return rc;
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mode |= FIELD_PREP(I2C_MODE_CLKDIV, I2C_DEFAULT_CLK_DIV);
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode);
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if (rc)
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return rc;
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rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_ESTAT, &extended_status);
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if (rc)
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return rc;
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i2c->fifo_size = FIELD_GET(I2C_ESTAT_FIFO_SZ, extended_status);
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watermark = FIELD_PREP(I2C_WATERMARK_HI,
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i2c->fifo_size - I2C_FIFO_HI_LVL);
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watermark |= FIELD_PREP(I2C_WATERMARK_LO, I2C_FIFO_LO_LVL);
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return fsi_i2c_write_reg(i2c->fsi, I2C_FSI_WATER_MARK, &watermark);
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}
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static int fsi_i2c_set_port(struct fsi_i2c_port *port)
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{
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int rc;
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struct fsi_device *fsi = port->master->fsi;
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u32 mode, dummy = 0;
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rc = fsi_i2c_read_reg(fsi, I2C_FSI_MODE, &mode);
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if (rc)
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return rc;
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if (FIELD_GET(I2C_MODE_PORT, mode) == port->port)
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return 0;
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mode = (mode & ~I2C_MODE_PORT) | FIELD_PREP(I2C_MODE_PORT, port->port);
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rc = fsi_i2c_write_reg(fsi, I2C_FSI_MODE, &mode);
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if (rc)
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return rc;
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/* reset engine when port is changed */
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return fsi_i2c_write_reg(fsi, I2C_FSI_RESET_ERR, &dummy);
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}
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static int fsi_i2c_start(struct fsi_i2c_port *port, struct i2c_msg *msg,
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bool stop)
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{
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struct fsi_i2c_master *i2c = port->master;
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u32 cmd = I2C_CMD_WITH_START | I2C_CMD_WITH_ADDR;
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port->xfrd = 0;
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if (msg->flags & I2C_M_RD)
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cmd |= I2C_CMD_READ;
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if (stop || msg->flags & I2C_M_STOP)
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cmd |= I2C_CMD_WITH_STOP;
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cmd |= FIELD_PREP(I2C_CMD_ADDR, msg->addr);
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cmd |= FIELD_PREP(I2C_CMD_LEN, msg->len);
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return fsi_i2c_write_reg(i2c->fsi, I2C_FSI_CMD, &cmd);
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}
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static int fsi_i2c_get_op_bytes(int op_bytes)
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{
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/* fsi is limited to max 4 byte aligned ops */
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if (op_bytes > 4)
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return 4;
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else if (op_bytes == 3)
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return 2;
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return op_bytes;
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}
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static int fsi_i2c_write_fifo(struct fsi_i2c_port *port, struct i2c_msg *msg,
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u8 fifo_count)
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{
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int write;
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int rc;
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struct fsi_i2c_master *i2c = port->master;
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int bytes_to_write = i2c->fifo_size - fifo_count;
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int bytes_remaining = msg->len - port->xfrd;
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bytes_to_write = min(bytes_to_write, bytes_remaining);
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while (bytes_to_write) {
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write = fsi_i2c_get_op_bytes(bytes_to_write);
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rc = fsi_device_write(i2c->fsi, I2C_FSI_FIFO,
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&msg->buf[port->xfrd], write);
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if (rc)
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return rc;
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port->xfrd += write;
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bytes_to_write -= write;
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}
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return 0;
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}
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static int fsi_i2c_read_fifo(struct fsi_i2c_port *port, struct i2c_msg *msg,
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u8 fifo_count)
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{
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int read;
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int rc;
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struct fsi_i2c_master *i2c = port->master;
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int bytes_to_read;
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int xfr_remaining = msg->len - port->xfrd;
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u32 dummy;
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bytes_to_read = min_t(int, fifo_count, xfr_remaining);
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while (bytes_to_read) {
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read = fsi_i2c_get_op_bytes(bytes_to_read);
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if (xfr_remaining) {
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rc = fsi_device_read(i2c->fsi, I2C_FSI_FIFO,
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&msg->buf[port->xfrd], read);
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if (rc)
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return rc;
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port->xfrd += read;
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xfr_remaining -= read;
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} else {
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/* no more buffer but data in fifo, need to clear it */
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rc = fsi_device_read(i2c->fsi, I2C_FSI_FIFO, &dummy,
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read);
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if (rc)
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return rc;
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}
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bytes_to_read -= read;
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}
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return 0;
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}
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static int fsi_i2c_get_scl(struct i2c_adapter *adap)
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{
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u32 stat = 0;
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struct fsi_i2c_port *port = adap->algo_data;
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struct fsi_i2c_master *i2c = port->master;
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fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat);
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return !!(stat & I2C_STAT_SCL_IN);
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}
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static void fsi_i2c_set_scl(struct i2c_adapter *adap, int val)
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{
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u32 dummy = 0;
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struct fsi_i2c_port *port = adap->algo_data;
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struct fsi_i2c_master *i2c = port->master;
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if (val)
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_SET_SCL, &dummy);
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else
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_SCL, &dummy);
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}
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static int fsi_i2c_get_sda(struct i2c_adapter *adap)
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{
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u32 stat = 0;
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struct fsi_i2c_port *port = adap->algo_data;
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struct fsi_i2c_master *i2c = port->master;
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fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat);
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return !!(stat & I2C_STAT_SDA_IN);
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}
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static void fsi_i2c_set_sda(struct i2c_adapter *adap, int val)
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{
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u32 dummy = 0;
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struct fsi_i2c_port *port = adap->algo_data;
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struct fsi_i2c_master *i2c = port->master;
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if (val)
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_SET_SDA, &dummy);
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else
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_SDA, &dummy);
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}
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static void fsi_i2c_prepare_recovery(struct i2c_adapter *adap)
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{
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int rc;
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u32 mode;
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struct fsi_i2c_port *port = adap->algo_data;
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struct fsi_i2c_master *i2c = port->master;
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rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode);
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if (rc)
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return;
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mode |= I2C_MODE_DIAG;
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode);
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}
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static void fsi_i2c_unprepare_recovery(struct i2c_adapter *adap)
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{
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int rc;
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u32 mode;
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struct fsi_i2c_port *port = adap->algo_data;
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struct fsi_i2c_master *i2c = port->master;
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rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode);
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if (rc)
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return;
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mode &= ~I2C_MODE_DIAG;
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fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode);
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}
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static int fsi_i2c_reset_bus(struct fsi_i2c_master *i2c,
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struct fsi_i2c_port *port)
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{
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int rc;
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u32 stat, dummy = 0;
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/* force bus reset, ignore errors */
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i2c_recover_bus(&port->adapter);
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/* reset errors */
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_ERR, &dummy);
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if (rc)
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return rc;
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/* wait for command complete */
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usleep_range(I2C_RESET_SLEEP_MIN_US, I2C_RESET_SLEEP_MAX_US);
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rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat);
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if (rc)
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return rc;
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if (stat & I2C_STAT_CMD_COMP)
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return 0;
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/* failed to get command complete; reset engine again */
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_I2C, &dummy);
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if (rc)
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return rc;
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/* re-init engine again */
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return fsi_i2c_dev_init(i2c);
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}
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static int fsi_i2c_reset_engine(struct fsi_i2c_master *i2c, u16 port)
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{
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int rc;
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u32 mode, dummy = 0;
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/* reset engine */
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rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_I2C, &dummy);
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if (rc)
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return rc;
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/* re-init engine */
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rc = fsi_i2c_dev_init(i2c);
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if (rc)
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return rc;
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rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode);
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if (rc)
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return rc;
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/* set port; default after reset is 0 */
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if (port) {
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mode &= ~I2C_MODE_PORT;
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|
mode |= FIELD_PREP(I2C_MODE_PORT, port);
|
|
rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
/* reset busy register; hw workaround */
|
|
dummy = I2C_PORT_BUSY_RESET;
|
|
rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_PORT_BUSY, &dummy);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int fsi_i2c_abort(struct fsi_i2c_port *port, u32 status)
|
|
{
|
|
int rc;
|
|
unsigned long start;
|
|
u32 cmd = I2C_CMD_WITH_STOP;
|
|
u32 stat;
|
|
struct fsi_i2c_master *i2c = port->master;
|
|
struct fsi_device *fsi = i2c->fsi;
|
|
|
|
rc = fsi_i2c_reset_engine(i2c, port->port);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = fsi_i2c_read_reg(fsi, I2C_FSI_STAT, &stat);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* if sda is low, peform full bus reset */
|
|
if (!(stat & I2C_STAT_SDA_IN)) {
|
|
rc = fsi_i2c_reset_bus(i2c, port);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
/* skip final stop command for these errors */
|
|
if (status & (I2C_STAT_PARITY | I2C_STAT_LOST_ARB | I2C_STAT_STOP_ERR))
|
|
return 0;
|
|
|
|
/* write stop command */
|
|
rc = fsi_i2c_write_reg(fsi, I2C_FSI_CMD, &cmd);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* wait until we see command complete in the master */
|
|
start = jiffies;
|
|
|
|
do {
|
|
rc = fsi_i2c_read_reg(fsi, I2C_FSI_STAT, &status);
|
|
if (rc)
|
|
return rc;
|
|
|
|
if (status & I2C_STAT_CMD_COMP)
|
|
return 0;
|
|
|
|
usleep_range(I2C_CMD_SLEEP_MIN_US, I2C_CMD_SLEEP_MAX_US);
|
|
} while (time_after(start + I2C_ABORT_TIMEOUT, jiffies));
|
|
|
|
return -ETIMEDOUT;
|
|
}
|
|
|
|
static int fsi_i2c_handle_status(struct fsi_i2c_port *port,
|
|
struct i2c_msg *msg, u32 status)
|
|
{
|
|
int rc;
|
|
u8 fifo_count;
|
|
|
|
if (status & I2C_STAT_ERR) {
|
|
rc = fsi_i2c_abort(port, status);
|
|
if (rc)
|
|
return rc;
|
|
|
|
if (status & I2C_STAT_INV_CMD)
|
|
return -EINVAL;
|
|
|
|
if (status & (I2C_STAT_PARITY | I2C_STAT_BE_OVERRUN |
|
|
I2C_STAT_BE_ACCESS))
|
|
return -EPROTO;
|
|
|
|
if (status & I2C_STAT_NACK)
|
|
return -ENXIO;
|
|
|
|
if (status & I2C_STAT_LOST_ARB)
|
|
return -EAGAIN;
|
|
|
|
if (status & I2C_STAT_STOP_ERR)
|
|
return -EBADMSG;
|
|
|
|
return -EIO;
|
|
}
|
|
|
|
if (status & I2C_STAT_DAT_REQ) {
|
|
fifo_count = FIELD_GET(I2C_STAT_FIFO_COUNT, status);
|
|
|
|
if (msg->flags & I2C_M_RD)
|
|
return fsi_i2c_read_fifo(port, msg, fifo_count);
|
|
|
|
return fsi_i2c_write_fifo(port, msg, fifo_count);
|
|
}
|
|
|
|
if (status & I2C_STAT_CMD_COMP) {
|
|
if (port->xfrd < msg->len)
|
|
return -ENODATA;
|
|
|
|
return msg->len;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int fsi_i2c_wait(struct fsi_i2c_port *port, struct i2c_msg *msg,
|
|
unsigned long timeout)
|
|
{
|
|
u32 status = 0;
|
|
int rc;
|
|
unsigned long start = jiffies;
|
|
|
|
do {
|
|
rc = fsi_i2c_read_reg(port->master->fsi, I2C_FSI_STAT,
|
|
&status);
|
|
if (rc)
|
|
return rc;
|
|
|
|
if (status & I2C_STAT_ANY_RESP) {
|
|
rc = fsi_i2c_handle_status(port, msg, status);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
/* cmd complete and all data xfrd */
|
|
if (rc == msg->len)
|
|
return 0;
|
|
|
|
/* need to xfr more data, but maybe don't need wait */
|
|
continue;
|
|
}
|
|
|
|
usleep_range(I2C_CMD_SLEEP_MIN_US, I2C_CMD_SLEEP_MAX_US);
|
|
} while (time_after(start + timeout, jiffies));
|
|
|
|
return -ETIMEDOUT;
|
|
}
|
|
|
|
static int fsi_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
|
|
int num)
|
|
{
|
|
int i, rc;
|
|
unsigned long start_time;
|
|
struct fsi_i2c_port *port = adap->algo_data;
|
|
struct fsi_i2c_master *master = port->master;
|
|
struct i2c_msg *msg;
|
|
|
|
mutex_lock(&master->lock);
|
|
|
|
rc = fsi_i2c_set_port(port);
|
|
if (rc)
|
|
goto unlock;
|
|
|
|
for (i = 0; i < num; i++) {
|
|
msg = msgs + i;
|
|
start_time = jiffies;
|
|
|
|
rc = fsi_i2c_start(port, msg, i == num - 1);
|
|
if (rc)
|
|
goto unlock;
|
|
|
|
rc = fsi_i2c_wait(port, msg,
|
|
adap->timeout - (jiffies - start_time));
|
|
if (rc)
|
|
goto unlock;
|
|
}
|
|
|
|
unlock:
|
|
mutex_unlock(&master->lock);
|
|
return rc ? : num;
|
|
}
|
|
|
|
static u32 fsi_i2c_functionality(struct i2c_adapter *adap)
|
|
{
|
|
return I2C_FUNC_I2C | I2C_FUNC_PROTOCOL_MANGLING |
|
|
I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA;
|
|
}
|
|
|
|
static struct i2c_bus_recovery_info fsi_i2c_bus_recovery_info = {
|
|
.recover_bus = i2c_generic_scl_recovery,
|
|
.get_scl = fsi_i2c_get_scl,
|
|
.set_scl = fsi_i2c_set_scl,
|
|
.get_sda = fsi_i2c_get_sda,
|
|
.set_sda = fsi_i2c_set_sda,
|
|
.prepare_recovery = fsi_i2c_prepare_recovery,
|
|
.unprepare_recovery = fsi_i2c_unprepare_recovery,
|
|
};
|
|
|
|
static const struct i2c_algorithm fsi_i2c_algorithm = {
|
|
.master_xfer = fsi_i2c_xfer,
|
|
.functionality = fsi_i2c_functionality,
|
|
};
|
|
|
|
static struct device_node *fsi_i2c_find_port_of_node(struct device_node *fsi,
|
|
int port)
|
|
{
|
|
struct device_node *np;
|
|
u32 port_no;
|
|
int rc;
|
|
|
|
for_each_child_of_node(fsi, np) {
|
|
rc = of_property_read_u32(np, "reg", &port_no);
|
|
if (!rc && port_no == port)
|
|
return np;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int fsi_i2c_probe(struct device *dev)
|
|
{
|
|
struct fsi_i2c_master *i2c;
|
|
struct fsi_i2c_port *port;
|
|
struct device_node *np;
|
|
u32 port_no, ports, stat;
|
|
int rc;
|
|
|
|
i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL);
|
|
if (!i2c)
|
|
return -ENOMEM;
|
|
|
|
mutex_init(&i2c->lock);
|
|
i2c->fsi = to_fsi_dev(dev);
|
|
INIT_LIST_HEAD(&i2c->ports);
|
|
|
|
rc = fsi_i2c_dev_init(i2c);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat);
|
|
if (rc)
|
|
return rc;
|
|
|
|
ports = FIELD_GET(I2C_STAT_MAX_PORT, stat) + 1;
|
|
dev_dbg(dev, "I2C master has %d ports\n", ports);
|
|
|
|
for (port_no = 0; port_no < ports; port_no++) {
|
|
np = fsi_i2c_find_port_of_node(dev->of_node, port_no);
|
|
if (np && !of_device_is_available(np))
|
|
continue;
|
|
|
|
port = kzalloc(sizeof(*port), GFP_KERNEL);
|
|
if (!port) {
|
|
of_node_put(np);
|
|
break;
|
|
}
|
|
|
|
port->master = i2c;
|
|
port->port = port_no;
|
|
|
|
port->adapter.owner = THIS_MODULE;
|
|
port->adapter.dev.of_node = np;
|
|
port->adapter.dev.parent = dev;
|
|
port->adapter.algo = &fsi_i2c_algorithm;
|
|
port->adapter.bus_recovery_info = &fsi_i2c_bus_recovery_info;
|
|
port->adapter.algo_data = port;
|
|
|
|
snprintf(port->adapter.name, sizeof(port->adapter.name),
|
|
"i2c_bus-%u", port_no);
|
|
|
|
rc = i2c_add_adapter(&port->adapter);
|
|
if (rc < 0) {
|
|
dev_err(dev, "Failed to register adapter: %d\n", rc);
|
|
kfree(port);
|
|
continue;
|
|
}
|
|
|
|
list_add(&port->list, &i2c->ports);
|
|
}
|
|
|
|
dev_set_drvdata(dev, i2c);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int fsi_i2c_remove(struct device *dev)
|
|
{
|
|
struct fsi_i2c_master *i2c = dev_get_drvdata(dev);
|
|
struct fsi_i2c_port *port, *tmp;
|
|
|
|
list_for_each_entry_safe(port, tmp, &i2c->ports, list) {
|
|
list_del(&port->list);
|
|
i2c_del_adapter(&port->adapter);
|
|
kfree(port);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct fsi_device_id fsi_i2c_ids[] = {
|
|
{ FSI_ENGID_I2C, FSI_VERSION_ANY },
|
|
{ }
|
|
};
|
|
|
|
static struct fsi_driver fsi_i2c_driver = {
|
|
.id_table = fsi_i2c_ids,
|
|
.drv = {
|
|
.name = "i2c-fsi",
|
|
.bus = &fsi_bus_type,
|
|
.probe = fsi_i2c_probe,
|
|
.remove = fsi_i2c_remove,
|
|
},
|
|
};
|
|
|
|
module_fsi_driver(fsi_i2c_driver);
|
|
|
|
MODULE_AUTHOR("Eddie James <eajames@us.ibm.com>");
|
|
MODULE_DESCRIPTION("FSI attached I2C master");
|
|
MODULE_LICENSE("GPL");
|