[U-Boot] [PATCH] i2c: Drop CONFIG_SYS_I2C_MXS

Tuomas Tynkkynen tuomas at tuxera.com
Wed Aug 15 23:08:11 UTC 2018


Last user of this driver went away in May 2017, in
commit eb5ba3aefdf0f6 ("i2c: Drop use of CONFIG_I2C_HARD")

Signed-off-by: Tuomas Tynkkynen <tuomas at tuxera.com>
---
 drivers/i2c/Makefile  |   1 -
 drivers/i2c/mxs_i2c.c | 319 --------------------------------------------------
 2 files changed, 320 deletions(-)
 delete mode 100644 drivers/i2c/mxs_i2c.c

diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index da368cc02a..f2cbe78c53 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -24,7 +24,6 @@ obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
 obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
 obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
 obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
-obj-$(CONFIG_SYS_I2C_MXS) += mxs_i2c.o
 obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
 obj-$(CONFIG_SYS_I2C_RCAR_I2C) += rcar_i2c.o
 obj-$(CONFIG_SYS_I2C_RCAR_IIC) += rcar_iic.o
diff --git a/drivers/i2c/mxs_i2c.c b/drivers/i2c/mxs_i2c.c
deleted file mode 100644
index 6766d37547..0000000000
--- a/drivers/i2c/mxs_i2c.c
+++ /dev/null
@@ -1,319 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-/*
- * Freescale i.MX28 I2C Driver
- *
- * Copyright (C) 2011 Marek Vasut <marek.vasut at gmail.com>
- * on behalf of DENX Software Engineering GmbH
- *
- * Partly based on Linux kernel i2c-mxs.c driver:
- * Copyright (C) 2011 Wolfram Sang, Pengutronix e.K.
- *
- * Which was based on a (non-working) driver which was:
- * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved.
- */
-
-#include <common.h>
-#include <malloc.h>
-#include <i2c.h>
-#include <linux/errno.h>
-#include <asm/io.h>
-#include <asm/arch/clock.h>
-#include <asm/arch/imx-regs.h>
-#include <asm/arch/sys_proto.h>
-
-#define	MXS_I2C_MAX_TIMEOUT	1000000
-
-static struct mxs_i2c_regs *mxs_i2c_get_base(struct i2c_adapter *adap)
-{
-	if (adap->hwadapnr == 0)
-		return (struct mxs_i2c_regs *)MXS_I2C0_BASE;
-	else
-		return (struct mxs_i2c_regs *)MXS_I2C1_BASE;
-}
-
-static unsigned int mxs_i2c_get_bus_speed(struct i2c_adapter *adap)
-{
-	struct mxs_i2c_regs *i2c_regs = mxs_i2c_get_base(adap);
-	uint32_t clk = mxc_get_clock(MXC_XTAL_CLK);
-	uint32_t timing0;
-
-	timing0 = readl(&i2c_regs->hw_i2c_timing0);
-	/*
-	 * This is a reverse version of the algorithm presented in
-	 * i2c_set_bus_speed(). Please refer there for details.
-	 */
-	return clk / ((((timing0 >> 16) - 3) * 2) + 38);
-}
-
-static uint mxs_i2c_set_bus_speed(struct i2c_adapter *adap, uint speed)
-{
-	struct mxs_i2c_regs *i2c_regs = mxs_i2c_get_base(adap);
-	/*
-	 * The timing derivation algorithm. There is no documentation for this
-	 * algorithm available, it was derived by using the scope and fiddling
-	 * with constants until the result observed on the scope was good enough
-	 * for 20kHz, 50kHz, 100kHz, 200kHz, 300kHz and 400kHz. It should be
-	 * possible to assume the algorithm works for other frequencies as well.
-	 *
-	 * Note it was necessary to cap the frequency on both ends as it's not
-	 * possible to configure completely arbitrary frequency for the I2C bus
-	 * clock.
-	 */
-	uint32_t clk = mxc_get_clock(MXC_XTAL_CLK);
-	uint32_t base = ((clk / speed) - 38) / 2;
-	uint16_t high_count = base + 3;
-	uint16_t low_count = base - 3;
-	uint16_t rcv_count = (high_count * 3) / 4;
-	uint16_t xmit_count = low_count / 4;
-
-	if (speed > 540000) {
-		printf("MXS I2C: Speed too high (%d Hz)\n", speed);
-		return -EINVAL;
-	}
-
-	if (speed < 12000) {
-		printf("MXS I2C: Speed too low (%d Hz)\n", speed);
-		return -EINVAL;
-	}
-
-	writel((high_count << 16) | rcv_count, &i2c_regs->hw_i2c_timing0);
-	writel((low_count << 16) | xmit_count, &i2c_regs->hw_i2c_timing1);
-
-	writel((0x0030 << I2C_TIMING2_BUS_FREE_OFFSET) |
-		(0x0030 << I2C_TIMING2_LEADIN_COUNT_OFFSET),
-		&i2c_regs->hw_i2c_timing2);
-
-	return 0;
-}
-
-static void mxs_i2c_reset(struct i2c_adapter *adap)
-{
-	struct mxs_i2c_regs *i2c_regs = mxs_i2c_get_base(adap);
-	int ret;
-	int speed = mxs_i2c_get_bus_speed(adap);
-
-	ret = mxs_reset_block(&i2c_regs->hw_i2c_ctrl0_reg);
-	if (ret) {
-		debug("MXS I2C: Block reset timeout\n");
-		return;
-	}
-
-	writel(I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ | I2C_CTRL1_NO_SLAVE_ACK_IRQ |
-		I2C_CTRL1_EARLY_TERM_IRQ | I2C_CTRL1_MASTER_LOSS_IRQ |
-		I2C_CTRL1_SLAVE_STOP_IRQ | I2C_CTRL1_SLAVE_IRQ,
-		&i2c_regs->hw_i2c_ctrl1_clr);
-
-	writel(I2C_QUEUECTRL_PIO_QUEUE_MODE, &i2c_regs->hw_i2c_queuectrl_set);
-
-	mxs_i2c_set_bus_speed(adap, speed);
-}
-
-static void mxs_i2c_setup_read(struct i2c_adapter *adap, uint8_t chip, int len)
-{
-	struct mxs_i2c_regs *i2c_regs = mxs_i2c_get_base(adap);
-
-	writel(I2C_QUEUECMD_RETAIN_CLOCK | I2C_QUEUECMD_PRE_SEND_START |
-		I2C_QUEUECMD_MASTER_MODE | I2C_QUEUECMD_DIRECTION |
-		(1 << I2C_QUEUECMD_XFER_COUNT_OFFSET),
-		&i2c_regs->hw_i2c_queuecmd);
-
-	writel((chip << 1) | 1, &i2c_regs->hw_i2c_data);
-
-	writel(I2C_QUEUECMD_SEND_NAK_ON_LAST | I2C_QUEUECMD_MASTER_MODE |
-		(len << I2C_QUEUECMD_XFER_COUNT_OFFSET) |
-		I2C_QUEUECMD_POST_SEND_STOP, &i2c_regs->hw_i2c_queuecmd);
-
-	writel(I2C_QUEUECTRL_QUEUE_RUN, &i2c_regs->hw_i2c_queuectrl_set);
-}
-
-static int mxs_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
-			 int alen, uchar *buf, int blen, int stop)
-{
-	struct mxs_i2c_regs *i2c_regs = mxs_i2c_get_base(adap);
-	uint32_t data, tmp;
-	int i, remain, off;
-	int timeout = MXS_I2C_MAX_TIMEOUT;
-
-	if ((alen > 4) || (alen == 0)) {
-		debug("MXS I2C: Invalid address length\n");
-		return -EINVAL;
-	}
-
-	if (stop)
-		stop = I2C_QUEUECMD_POST_SEND_STOP;
-
-	writel(I2C_QUEUECMD_PRE_SEND_START |
-		I2C_QUEUECMD_MASTER_MODE | I2C_QUEUECMD_DIRECTION |
-		((blen + alen + 1) << I2C_QUEUECMD_XFER_COUNT_OFFSET) | stop,
-		&i2c_regs->hw_i2c_queuecmd);
-
-	data = (chip << 1) << 24;
-
-	for (i = 0; i < alen; i++) {
-		data >>= 8;
-		data |= ((char *)&addr)[alen - i - 1] << 24;
-		if ((i & 3) == 2)
-			writel(data, &i2c_regs->hw_i2c_data);
-	}
-
-	off = i;
-	for (; i < off + blen; i++) {
-		data >>= 8;
-		data |= buf[i - off] << 24;
-		if ((i & 3) == 2)
-			writel(data, &i2c_regs->hw_i2c_data);
-	}
-
-	remain = 24 - ((i & 3) * 8);
-	if (remain)
-		writel(data >> remain, &i2c_regs->hw_i2c_data);
-
-	writel(I2C_QUEUECTRL_QUEUE_RUN, &i2c_regs->hw_i2c_queuectrl_set);
-
-	while (--timeout) {
-		tmp = readl(&i2c_regs->hw_i2c_queuestat);
-		if (tmp & I2C_QUEUESTAT_WR_QUEUE_EMPTY)
-			break;
-	}
-
-	if (!timeout) {
-		debug("MXS I2C: Failed transmitting data!\n");
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-static int mxs_i2c_wait_for_ack(struct i2c_adapter *adap)
-{
-	struct mxs_i2c_regs *i2c_regs = mxs_i2c_get_base(adap);
-	uint32_t tmp;
-	int timeout = MXS_I2C_MAX_TIMEOUT;
-
-	for (;;) {
-		tmp = readl(&i2c_regs->hw_i2c_ctrl1);
-		if (tmp & I2C_CTRL1_NO_SLAVE_ACK_IRQ) {
-			debug("MXS I2C: No slave ACK\n");
-			goto err;
-		}
-
-		if (tmp & (
-			I2C_CTRL1_EARLY_TERM_IRQ | I2C_CTRL1_MASTER_LOSS_IRQ |
-			I2C_CTRL1_SLAVE_STOP_IRQ | I2C_CTRL1_SLAVE_IRQ)) {
-			debug("MXS I2C: Error (CTRL1 = %08x)\n", tmp);
-			goto err;
-		}
-
-		if (tmp & I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ)
-			break;
-
-		if (!timeout--) {
-			debug("MXS I2C: Operation timed out\n");
-			goto err;
-		}
-
-		udelay(1);
-	}
-
-	return 0;
-
-err:
-	mxs_i2c_reset(adap);
-	return 1;
-}
-
-static int mxs_i2c_if_read(struct i2c_adapter *adap, uint8_t chip,
-			   uint addr, int alen, uint8_t *buffer,
-			   int len)
-{
-	struct mxs_i2c_regs *i2c_regs = mxs_i2c_get_base(adap);
-	uint32_t tmp = 0;
-	int timeout = MXS_I2C_MAX_TIMEOUT;
-	int ret;
-	int i;
-
-	ret = mxs_i2c_write(adap, chip, addr, alen, NULL, 0, 0);
-	if (ret) {
-		debug("MXS I2C: Failed writing address\n");
-		return ret;
-	}
-
-	ret = mxs_i2c_wait_for_ack(adap);
-	if (ret) {
-		debug("MXS I2C: Failed writing address\n");
-		return ret;
-	}
-
-	mxs_i2c_setup_read(adap, chip, len);
-	ret = mxs_i2c_wait_for_ack(adap);
-	if (ret) {
-		debug("MXS I2C: Failed reading address\n");
-		return ret;
-	}
-
-	for (i = 0; i < len; i++) {
-		if (!(i & 3)) {
-			while (--timeout) {
-				tmp = readl(&i2c_regs->hw_i2c_queuestat);
-				if (!(tmp & I2C_QUEUESTAT_RD_QUEUE_EMPTY))
-					break;
-			}
-
-			if (!timeout) {
-				debug("MXS I2C: Failed receiving data!\n");
-				return -ETIMEDOUT;
-			}
-
-			tmp = readl(&i2c_regs->hw_i2c_queuedata);
-		}
-		buffer[i] = tmp & 0xff;
-		tmp >>= 8;
-	}
-
-	return 0;
-}
-
-static int mxs_i2c_if_write(struct i2c_adapter *adap, uint8_t chip,
-			    uint addr, int alen, uint8_t *buffer,
-			    int len)
-{
-	int ret;
-	ret = mxs_i2c_write(adap, chip, addr, alen, buffer, len, 1);
-	if (ret) {
-		debug("MXS I2C: Failed writing address\n");
-		return ret;
-	}
-
-	ret = mxs_i2c_wait_for_ack(adap);
-	if (ret)
-		debug("MXS I2C: Failed writing address\n");
-
-	return ret;
-}
-
-static int mxs_i2c_probe(struct i2c_adapter *adap, uint8_t chip)
-{
-	int ret;
-	ret = mxs_i2c_write(adap, chip, 0, 1, NULL, 0, 1);
-	if (!ret)
-		ret = mxs_i2c_wait_for_ack(adap);
-	mxs_i2c_reset(adap);
-	return ret;
-}
-
-static void mxs_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
-{
-	mxs_i2c_reset(adap);
-	mxs_i2c_set_bus_speed(adap, speed);
-
-	return;
-}
-
-U_BOOT_I2C_ADAP_COMPLETE(mxs0, mxs_i2c_init, mxs_i2c_probe,
-			 mxs_i2c_if_read, mxs_i2c_if_write,
-			 mxs_i2c_set_bus_speed,
-			 CONFIG_SYS_I2C_SPEED, 0, 0)
-U_BOOT_I2C_ADAP_COMPLETE(mxs1, mxs_i2c_init, mxs_i2c_probe,
-			 mxs_i2c_if_read, mxs_i2c_if_write,
-			 mxs_i2c_set_bus_speed,
-			 CONFIG_SYS_I2C_SPEED, 0, 1)
-- 
2.16.3



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