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u-boot/drivers/i2c/rcar_i2c.c
Simon Glass 2852709676 dm: i2c: Add a note to I2C drivers which need conversion 
Maintainers need to be notified more directly of the need to convert these
drivers. Add a note to the top each affected file.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heiko Schocher <hs@denx.de>
2016-12-05 13:28:03 +01:00

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/*
* drivers/i2c/rcar_i2c.c
*
* Copyright (C) 2013 Renesas Electronics Corporation
* Copyright (C) 2013 Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
*
* SPDX-License-Identifier: GPL-2.0
*
* NOTE: This driver should be converted to driver model before June 2017.
* Please see doc/driver-model/i2c-howto.txt for instructions.
*/
#include <common.h>
#include <i2c.h>
#include <asm/io.h>
DECLARE_GLOBAL_DATA_PTR;
struct rcar_i2c {
u32 icscr;
u32 icmcr;
u32 icssr;
u32 icmsr;
u32 icsier;
u32 icmier;
u32 icccr;
u32 icsar;
u32 icmar;
u32 icrxdtxd;
u32 icccr2;
u32 icmpr;
u32 ichpr;
u32 iclpr;
};
#define MCR_MDBS 0x80 /* non-fifo mode switch */
#define MCR_FSCL 0x40 /* override SCL pin */
#define MCR_FSDA 0x20 /* override SDA pin */
#define MCR_OBPC 0x10 /* override pins */
#define MCR_MIE 0x08 /* master if enable */
#define MCR_TSBE 0x04
#define MCR_FSB 0x02 /* force stop bit */
#define MCR_ESG 0x01 /* en startbit gen. */
#define MSR_MASK 0x7f
#define MSR_MNR 0x40 /* nack received */
#define MSR_MAL 0x20 /* arbitration lost */
#define MSR_MST 0x10 /* sent a stop */
#define MSR_MDE 0x08
#define MSR_MDT 0x04
#define MSR_MDR 0x02
#define MSR_MAT 0x01 /* slave addr xfer done */
static const struct rcar_i2c *i2c_dev[CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS] = {
(struct rcar_i2c *)CONFIG_SYS_RCAR_I2C0_BASE,
(struct rcar_i2c *)CONFIG_SYS_RCAR_I2C1_BASE,
(struct rcar_i2c *)CONFIG_SYS_RCAR_I2C2_BASE,
(struct rcar_i2c *)CONFIG_SYS_RCAR_I2C3_BASE,
};
static void rcar_i2c_raw_rw_common(struct rcar_i2c *dev, u8 chip, uint addr)
{
/* set slave address */
writel(chip << 1, &dev->icmar);
/* set register address */
writel(addr, &dev->icrxdtxd);
/* clear status */
writel(0, &dev->icmsr);
/* start master send */
writel(MCR_MDBS | MCR_MIE | MCR_ESG, &dev->icmcr);
while ((readl(&dev->icmsr) & (MSR_MAT | MSR_MDE))
!= (MSR_MAT | MSR_MDE))
udelay(10);
/* clear ESG */
writel(MCR_MDBS | MCR_MIE, &dev->icmcr);
/* start SCLclk */
writel(~(MSR_MAT | MSR_MDE), &dev->icmsr);
while (!(readl(&dev->icmsr) & MSR_MDE))
udelay(10);
}
static void rcar_i2c_raw_rw_finish(struct rcar_i2c *dev)
{
while (!(readl(&dev->icmsr) & MSR_MST))
udelay(10);
writel(0, &dev->icmcr);
}
static int
rcar_i2c_raw_write(struct rcar_i2c *dev, u8 chip, uint addr, u8 *val, int size)
{
rcar_i2c_raw_rw_common(dev, chip, addr);
/* set send date */
writel(*val, &dev->icrxdtxd);
/* start SCLclk */
writel(~MSR_MDE, &dev->icmsr);
while (!(readl(&dev->icmsr) & MSR_MDE))
udelay(10);
/* set stop condition */
writel(MCR_MDBS | MCR_MIE | MCR_FSB, &dev->icmcr);
/* start SCLclk */
writel(~MSR_MDE, &dev->icmsr);
rcar_i2c_raw_rw_finish(dev);
return 0;
}
static u8
rcar_i2c_raw_read(struct rcar_i2c *dev, u8 chip, uint addr)
{
u8 ret;
rcar_i2c_raw_rw_common(dev, chip, addr);
/* set slave address, receive */
writel((chip << 1) | 1, &dev->icmar);
/* start master receive */
writel(MCR_MDBS | MCR_MIE | MCR_ESG, &dev->icmcr);
/* clear status */
writel(0, &dev->icmsr);
while ((readl(&dev->icmsr) & (MSR_MAT | MSR_MDR))
!= (MSR_MAT | MSR_MDR))
udelay(10);
/* clear ESG */
writel(MCR_MDBS | MCR_MIE, &dev->icmcr);
/* prepare stop condition */
writel(MCR_MDBS | MCR_MIE | MCR_FSB, &dev->icmcr);
/* start SCLclk */
writel(~(MSR_MAT | MSR_MDR), &dev->icmsr);
while (!(readl(&dev->icmsr) & MSR_MDR))
udelay(10);
/* get receive data */
ret = (u8)readl(&dev->icrxdtxd);
/* start SCLclk */
writel(~MSR_MDR, &dev->icmsr);
rcar_i2c_raw_rw_finish(dev);
return ret;
}
/*
* SCL = iicck / (20 + SCGD * 8 + F[(ticf + tr + intd) * iicck])
* iicck : I2C internal clock < 20 MHz
* ticf : I2C SCL falling time: 35 ns
* tr : I2C SCL rising time: 200 ns
* intd : LSI internal delay: I2C0: 50 ns I2C1-3: 5
* F[n] : n rounded up to an integer
*/
static u32 rcar_clock_gen(int i2c_no, u32 bus_speed)
{
u32 iicck, f, scl, scgd;
u32 intd = 5;
int bit = 0, cdf_width = 3;
for (bit = 0; bit < (1 << cdf_width); bit++) {
iicck = CONFIG_HP_CLK_FREQ / (1 + bit);
if (iicck < 20000000)
break;
}
if (bit > (1 << cdf_width)) {
puts("rcar-i2c: Can not get CDF\n");
return 0;
}
if (i2c_no == 0)
intd = 50;
f = (35 + 200 + intd) * (iicck / 1000000000);
for (scgd = 0; scgd < 0x40; scgd++) {
scl = iicck / (20 + (scgd * 8) + f);
if (scl <= bus_speed)
break;
}
if (scgd > 0x40) {
puts("rcar-i2c: Can not get SDGB\n");
return 0;
}
debug("%s: scl: %d\n", __func__, scl);
debug("%s: bit %x\n", __func__, bit);
debug("%s: scgd %x\n", __func__, scgd);
debug("%s: iccr %x\n", __func__, (scgd << (cdf_width) | bit));
return scgd << (cdf_width) | bit;
}
static void
rcar_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
{
struct rcar_i2c *dev = (struct rcar_i2c *)i2c_dev[adap->hwadapnr];
u32 icccr = 0;
/* No i2c support prior to relocation */
if (!(gd->flags & GD_FLG_RELOC))
return;
/*
* reset slave mode.
* slave mode is not used on this driver
*/
writel(0, &dev->icsier);
writel(0, &dev->icsar);
writel(0, &dev->icscr);
writel(0, &dev->icssr);
/* reset master mode */
writel(0, &dev->icmier);
writel(0, &dev->icmcr);
writel(0, &dev->icmsr);
writel(0, &dev->icmar);
icccr = rcar_clock_gen(adap->hwadapnr, adap->speed);
if (icccr == 0)
puts("I2C: Init failed\n");
else
writel(icccr, &dev->icccr);
}
static int rcar_i2c_read(struct i2c_adapter *adap, uint8_t chip,
uint addr, int alen, u8 *data, int len)
{
struct rcar_i2c *dev = (struct rcar_i2c *)i2c_dev[adap->hwadapnr];
int i;
for (i = 0; i < len; i++)
data[i] = rcar_i2c_raw_read(dev, chip, addr + i);
return 0;
}
static int rcar_i2c_write(struct i2c_adapter *adap, uint8_t chip, uint addr,
int alen, u8 *data, int len)
{
struct rcar_i2c *dev = (struct rcar_i2c *)i2c_dev[adap->hwadapnr];
return rcar_i2c_raw_write(dev, chip, addr, data, len);
}
static int
rcar_i2c_probe(struct i2c_adapter *adap, u8 dev)
{
return rcar_i2c_read(adap, dev, 0, 0, NULL, 0);
}
static unsigned int rcar_i2c_set_bus_speed(struct i2c_adapter *adap,
unsigned int speed)
{
struct rcar_i2c *dev = (struct rcar_i2c *)i2c_dev[adap->hwadapnr];
u32 icccr;
int ret = 0;
rcar_i2c_raw_rw_finish(dev);
icccr = rcar_clock_gen(adap->hwadapnr, speed);
if (icccr == 0) {
puts("I2C: Init failed\n");
ret = -1;
} else {
writel(icccr, &dev->icccr);
}
return ret;
}
/*
* Register RCAR i2c adapters
*/
U_BOOT_I2C_ADAP_COMPLETE(rcar_0, rcar_i2c_init, rcar_i2c_probe, rcar_i2c_read,
rcar_i2c_write, rcar_i2c_set_bus_speed,
CONFIG_SYS_RCAR_I2C0_SPEED, 0, 0)
U_BOOT_I2C_ADAP_COMPLETE(rcar_1, rcar_i2c_init, rcar_i2c_probe, rcar_i2c_read,
rcar_i2c_write, rcar_i2c_set_bus_speed,
CONFIG_SYS_RCAR_I2C1_SPEED, 0, 1)
U_BOOT_I2C_ADAP_COMPLETE(rcar_2, rcar_i2c_init, rcar_i2c_probe, rcar_i2c_read,
rcar_i2c_write, rcar_i2c_set_bus_speed,
CONFIG_SYS_RCAR_I2C2_SPEED, 0, 2)
U_BOOT_I2C_ADAP_COMPLETE(rcar_3, rcar_i2c_init, rcar_i2c_probe, rcar_i2c_read,
rcar_i2c_write, rcar_i2c_set_bus_speed,
CONFIG_SYS_RCAR_I2C3_SPEED, 0, 3)
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