mfd: Add realtek USB card reader driver

Realtek USB card reader provides a channel to transfer command or data to flash
memory cards. This driver exports host instances for mmc and memstick subsystems
and handles basic works.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Roger Tseng <rogerable@realtek.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 760 insertions, 0 deletions

diff --git a/drivers/mfd/rtsx_usb.c b/drivers/mfd/rtsx_usb.c
new file mode 100644
index 000000000000..b53b9d46cc45
--- /dev/null
+++ b/drivers/mfd/rtsx_usb.c
@@ -0,0 +1,760 @@
+/* Driver for Realtek USB card reader
+ *
+ * Copyright(c) 2009-2013 Realtek Semiconductor Corp. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author:
+ *   Roger Tseng <rogerable@realtek.com>
+ */
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/usb.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/rtsx_usb.h>
+
+static int polling_pipe = 1;
+module_param(polling_pipe, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(polling_pipe, "polling pipe (0: ctl, 1: bulk)");
+
+static struct mfd_cell rtsx_usb_cells[] = {
+	[RTSX_USB_SD_CARD] = {
+		.name = "rtsx_usb_sdmmc",
+		.pdata_size = 0,
+	},
+	[RTSX_USB_MS_CARD] = {
+		.name = "rtsx_usb_ms",
+		.pdata_size = 0,
+	},
+};
+
+static void rtsx_usb_sg_timed_out(unsigned long data)
+{
+	struct rtsx_ucr *ucr = (struct rtsx_ucr *)data;
+
+	dev_dbg(&ucr->pusb_intf->dev, "%s: sg transfer timed out", __func__);
+	usb_sg_cancel(&ucr->current_sg);
+
+	/* we know the cancellation is caused by time-out */
+	ucr->current_sg.status = -ETIMEDOUT;
+}
+
+static int rtsx_usb_bulk_transfer_sglist(struct rtsx_ucr *ucr,
+		unsigned int pipe, struct scatterlist *sg, int num_sg,
+		unsigned int length, unsigned int *act_len, int timeout)
+{
+	int ret;
+
+	dev_dbg(&ucr->pusb_intf->dev, "%s: xfer %u bytes, %d entries\n",
+			__func__, length, num_sg);
+	ret = usb_sg_init(&ucr->current_sg, ucr->pusb_dev, pipe, 0,
+			sg, num_sg, length, GFP_NOIO);
+	if (ret)
+		return ret;
+
+	ucr->sg_timer.expires = jiffies + msecs_to_jiffies(timeout);
+	add_timer(&ucr->sg_timer);
+	usb_sg_wait(&ucr->current_sg);
+	del_timer(&ucr->sg_timer);
+
+	if (act_len)
+		*act_len = ucr->current_sg.bytes;
+
+	return ucr->current_sg.status;
+}
+
+int rtsx_usb_transfer_data(struct rtsx_ucr *ucr, unsigned int pipe,
+			      void *buf, unsigned int len, int num_sg,
+			      unsigned int *act_len, int timeout)
+{
+	if (timeout < 600)
+		timeout = 600;
+
+	if (num_sg)
+		return rtsx_usb_bulk_transfer_sglist(ucr, pipe,
+				(struct scatterlist *)buf, num_sg, len, act_len,
+				timeout);
+	else
+		return usb_bulk_msg(ucr->pusb_dev, pipe, buf, len, act_len,
+				timeout);
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_transfer_data);
+
+static inline void rtsx_usb_seq_cmd_hdr(struct rtsx_ucr *ucr,
+		u16 addr, u16 len, u8 seq_type)
+{
+	rtsx_usb_cmd_hdr_tag(ucr);
+
+	ucr->cmd_buf[PACKET_TYPE] = seq_type;
+	ucr->cmd_buf[5] = (u8)(len >> 8);
+	ucr->cmd_buf[6] = (u8)len;
+	ucr->cmd_buf[8] = (u8)(addr >> 8);
+	ucr->cmd_buf[9] = (u8)addr;
+
+	if (seq_type == SEQ_WRITE)
+		ucr->cmd_buf[STAGE_FLAG] = 0;
+	else
+		ucr->cmd_buf[STAGE_FLAG] = STAGE_R;
+}
+
+static int rtsx_usb_seq_write_register(struct rtsx_ucr *ucr,
+		u16 addr, u16 len, u8 *data)
+{
+	u16 cmd_len = ALIGN(SEQ_WRITE_DATA_OFFSET + len, 4);
+
+	if (!data)
+		return -EINVAL;
+
+	if (cmd_len > IOBUF_SIZE)
+		return -EINVAL;
+
+	rtsx_usb_seq_cmd_hdr(ucr, addr, len, SEQ_WRITE);
+	memcpy(ucr->cmd_buf + SEQ_WRITE_DATA_OFFSET, data, len);
+
+	return rtsx_usb_transfer_data(ucr,
+			usb_sndbulkpipe(ucr->pusb_dev, EP_BULK_OUT),
+			ucr->cmd_buf, cmd_len, 0, NULL, 100);
+}
+
+static int rtsx_usb_seq_read_register(struct rtsx_ucr *ucr,
+		u16 addr, u16 len, u8 *data)
+{
+	int i, ret;
+	u16 rsp_len = round_down(len, 4);
+	u16 res_len = len - rsp_len;
+
+	if (!data)
+		return -EINVAL;
+
+	/* 4-byte aligned part */
+	if (rsp_len) {
+		rtsx_usb_seq_cmd_hdr(ucr, addr, len, SEQ_READ);
+		ret = rtsx_usb_transfer_data(ucr,
+				usb_sndbulkpipe(ucr->pusb_dev, EP_BULK_OUT),
+				ucr->cmd_buf, 12, 0, NULL, 100);
+		if (ret)
+			return ret;
+
+		ret = rtsx_usb_transfer_data(ucr,
+				usb_rcvbulkpipe(ucr->pusb_dev, EP_BULK_IN),
+				data, rsp_len, 0, NULL, 100);
+		if (ret)
+			return ret;
+	}
+
+	/* unaligned part */
+	for (i = 0; i < res_len; i++) {
+		ret = rtsx_usb_read_register(ucr, addr + rsp_len + i,
+				data + rsp_len + i);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+int rtsx_usb_read_ppbuf(struct rtsx_ucr *ucr, u8 *buf, int buf_len)
+{
+	return rtsx_usb_seq_read_register(ucr, PPBUF_BASE2, (u16)buf_len, buf);
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_read_ppbuf);
+
+int rtsx_usb_write_ppbuf(struct rtsx_ucr *ucr, u8 *buf, int buf_len)
+{
+	return rtsx_usb_seq_write_register(ucr, PPBUF_BASE2, (u16)buf_len, buf);
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_write_ppbuf);
+
+int rtsx_usb_ep0_write_register(struct rtsx_ucr *ucr, u16 addr,
+		u8 mask, u8 data)
+{
+	u16 value, index;
+
+	addr |= EP0_WRITE_REG_CMD << EP0_OP_SHIFT;
+	value = swab16(addr);
+	index = mask | data << 8;
+
+	return usb_control_msg(ucr->pusb_dev,
+			usb_sndctrlpipe(ucr->pusb_dev, 0), RTSX_USB_REQ_REG_OP,
+			USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+			value, index, NULL, 0, 100);
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_ep0_write_register);
+
+int rtsx_usb_ep0_read_register(struct rtsx_ucr *ucr, u16 addr, u8 *data)
+{
+	u16 value;
+
+	if (!data)
+		return -EINVAL;
+	*data = 0;
+
+	addr |= EP0_READ_REG_CMD << EP0_OP_SHIFT;
+	value = swab16(addr);
+
+	return usb_control_msg(ucr->pusb_dev,
+			usb_rcvctrlpipe(ucr->pusb_dev, 0), RTSX_USB_REQ_REG_OP,
+			USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+			value, 0, data, 1, 100);
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_ep0_read_register);
+
+void rtsx_usb_add_cmd(struct rtsx_ucr *ucr, u8 cmd_type, u16 reg_addr,
+		u8 mask, u8 data)
+{
+	int i;
+
+	if (ucr->cmd_idx < (IOBUF_SIZE - CMD_OFFSET) / 4) {
+		i = CMD_OFFSET + ucr->cmd_idx * 4;
+
+		ucr->cmd_buf[i++] = ((cmd_type & 0x03) << 6) |
+			(u8)((reg_addr >> 8) & 0x3F);
+		ucr->cmd_buf[i++] = (u8)reg_addr;
+		ucr->cmd_buf[i++] = mask;
+		ucr->cmd_buf[i++] = data;
+
+		ucr->cmd_idx++;
+	}
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_add_cmd);
+
+int rtsx_usb_send_cmd(struct rtsx_ucr *ucr, u8 flag, int timeout)
+{
+	int ret;
+
+	ucr->cmd_buf[CNT_H] = (u8)(ucr->cmd_idx >> 8);
+	ucr->cmd_buf[CNT_L] = (u8)(ucr->cmd_idx);
+	ucr->cmd_buf[STAGE_FLAG] = flag;
+
+	ret = rtsx_usb_transfer_data(ucr,
+			usb_sndbulkpipe(ucr->pusb_dev, EP_BULK_OUT),
+			ucr->cmd_buf, ucr->cmd_idx * 4 + CMD_OFFSET,
+			0, NULL, timeout);
+	if (ret) {
+		rtsx_usb_clear_fsm_err(ucr);
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_send_cmd);
+
+int rtsx_usb_get_rsp(struct rtsx_ucr *ucr, int rsp_len, int timeout)
+{
+	if (rsp_len <= 0)
+		return -EINVAL;
+
+	rsp_len = ALIGN(rsp_len, 4);
+
+	return rtsx_usb_transfer_data(ucr,
+			usb_rcvbulkpipe(ucr->pusb_dev, EP_BULK_IN),
+			ucr->rsp_buf, rsp_len, 0, NULL, timeout);
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_get_rsp);
+
+static int rtsx_usb_get_status_with_bulk(struct rtsx_ucr *ucr, u16 *status)
+{
+	int ret;
+
+	rtsx_usb_init_cmd(ucr);
+	rtsx_usb_add_cmd(ucr, READ_REG_CMD, CARD_EXIST, 0x00, 0x00);
+	rtsx_usb_add_cmd(ucr, READ_REG_CMD, OCPSTAT, 0x00, 0x00);
+	ret = rtsx_usb_send_cmd(ucr, MODE_CR, 100);
+	if (ret)
+		return ret;
+
+	ret = rtsx_usb_get_rsp(ucr, 2, 100);
+	if (ret)
+		return ret;
+
+	*status = ((ucr->rsp_buf[0] >> 2) & 0x0f) |
+		  ((ucr->rsp_buf[1] & 0x03) << 4);
+
+	return 0;
+}
+
+int rtsx_usb_get_card_status(struct rtsx_ucr *ucr, u16 *status)
+{
+	int ret;
+
+	if (!status)
+		return -EINVAL;
+
+	if (polling_pipe == 0)
+		ret = usb_control_msg(ucr->pusb_dev,
+				usb_rcvctrlpipe(ucr->pusb_dev, 0),
+				RTSX_USB_REQ_POLL,
+				USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+				0, 0, status, 2, 100);
+	else
+		ret = rtsx_usb_get_status_with_bulk(ucr, status);
+
+	/* usb_control_msg may return positive when success */
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_get_card_status);
+
+static int rtsx_usb_write_phy_register(struct rtsx_ucr *ucr, u8 addr, u8 val)
+{
+	dev_dbg(&ucr->pusb_intf->dev, "Write 0x%x to phy register 0x%x\n",
+			val, addr);
+
+	rtsx_usb_init_cmd(ucr);
+
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, HS_VSTAIN, 0xFF, val);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, HS_VCONTROL, 0xFF, addr & 0x0F);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, HS_VLOADM, 0xFF, 0x00);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, HS_VLOADM, 0xFF, 0x00);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, HS_VLOADM, 0xFF, 0x01);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, HS_VCONTROL,
+			0xFF, (addr >> 4) & 0x0F);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, HS_VLOADM, 0xFF, 0x00);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, HS_VLOADM, 0xFF, 0x00);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, HS_VLOADM, 0xFF, 0x01);
+
+	return rtsx_usb_send_cmd(ucr, MODE_C, 100);
+}
+
+int rtsx_usb_write_register(struct rtsx_ucr *ucr, u16 addr, u8 mask, u8 data)
+{
+	rtsx_usb_init_cmd(ucr);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, addr, mask, data);
+	return rtsx_usb_send_cmd(ucr, MODE_C, 100);
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_write_register);
+
+int rtsx_usb_read_register(struct rtsx_ucr *ucr, u16 addr, u8 *data)
+{
+	int ret;
+
+	if (data != NULL)
+		*data = 0;
+
+	rtsx_usb_init_cmd(ucr);
+	rtsx_usb_add_cmd(ucr, READ_REG_CMD, addr, 0, 0);
+	ret = rtsx_usb_send_cmd(ucr, MODE_CR, 100);
+	if (ret)
+		return ret;
+
+	ret = rtsx_usb_get_rsp(ucr, 1, 100);
+	if (ret)
+		return ret;
+
+	if (data != NULL)
+		*data = ucr->rsp_buf[0];
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_read_register);
+
+static inline u8 double_ssc_depth(u8 depth)
+{
+	return (depth > 1) ? (depth - 1) : depth;
+}
+
+static u8 revise_ssc_depth(u8 ssc_depth, u8 div)
+{
+	if (div > CLK_DIV_1) {
+		if (ssc_depth > div - 1)
+			ssc_depth -= (div - 1);
+		else
+			ssc_depth = SSC_DEPTH_2M;
+	}
+
+	return ssc_depth;
+}
+
+int rtsx_usb_switch_clock(struct rtsx_ucr *ucr, unsigned int card_clock,
+		u8 ssc_depth, bool initial_mode, bool double_clk, bool vpclk)
+{
+	int ret;
+	u8 n, clk_divider, mcu_cnt, div;
+
+	if (!card_clock) {
+		ucr->cur_clk = 0;
+		return 0;
+	}
+
+	if (initial_mode) {
+		/* We use 250k(around) here, in initial stage */
+		clk_divider = SD_CLK_DIVIDE_128;
+		card_clock = 30000000;
+	} else {
+		clk_divider = SD_CLK_DIVIDE_0;
+	}
+
+	ret = rtsx_usb_write_register(ucr, SD_CFG1,
+			SD_CLK_DIVIDE_MASK, clk_divider);
+	if (ret < 0)
+		return ret;
+
+	card_clock /= 1000000;
+	dev_dbg(&ucr->pusb_intf->dev,
+			"Switch card clock to %dMHz\n", card_clock);
+
+	if (!initial_mode && double_clk)
+		card_clock *= 2;
+	dev_dbg(&ucr->pusb_intf->dev,
+			"Internal SSC clock: %dMHz (cur_clk = %d)\n",
+			card_clock, ucr->cur_clk);
+
+	if (card_clock == ucr->cur_clk)
+		return 0;
+
+	/* Converting clock value into internal settings: n and div */
+	n = card_clock - 2;
+	if ((card_clock <= 2) || (n > MAX_DIV_N))
+		return -EINVAL;
+
+	mcu_cnt = 60/card_clock + 3;
+	if (mcu_cnt > 15)
+		mcu_cnt = 15;
+
+	/* Make sure that the SSC clock div_n is not less than MIN_DIV_N */
+
+	div = CLK_DIV_1;
+	while (n < MIN_DIV_N && div < CLK_DIV_4) {
+		n = (n + 2) * 2 - 2;
+		div++;
+	}
+	dev_dbg(&ucr->pusb_intf->dev, "n = %d, div = %d\n", n, div);
+
+	if (double_clk)
+		ssc_depth = double_ssc_depth(ssc_depth);
+
+	ssc_depth = revise_ssc_depth(ssc_depth, div);
+	dev_dbg(&ucr->pusb_intf->dev, "ssc_depth = %d\n", ssc_depth);
+
+	rtsx_usb_init_cmd(ucr);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, CLK_DIV, CLK_CHANGE, CLK_CHANGE);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, CLK_DIV,
+			0x3F, (div << 4) | mcu_cnt);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, SSC_CTL1, SSC_RSTB, 0);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, SSC_CTL2,
+			SSC_DEPTH_MASK, ssc_depth);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, SSC_DIV_N_0, 0xFF, n);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, SSC_CTL1, SSC_RSTB, SSC_RSTB);
+	if (vpclk) {
+		rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, SD_VPCLK0_CTL,
+				PHASE_NOT_RESET, 0);
+		rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, SD_VPCLK0_CTL,
+				PHASE_NOT_RESET, PHASE_NOT_RESET);
+	}
+
+	ret = rtsx_usb_send_cmd(ucr, MODE_C, 2000);
+	if (ret < 0)
+		return ret;
+
+	ret = rtsx_usb_write_register(ucr, SSC_CTL1, 0xff,
+			SSC_RSTB | SSC_8X_EN | SSC_SEL_4M);
+	if (ret < 0)
+		return ret;
+
+	/* Wait SSC clock stable */
+	usleep_range(100, 1000);
+
+	ret = rtsx_usb_write_register(ucr, CLK_DIV, CLK_CHANGE, 0);
+	if (ret < 0)
+		return ret;
+
+	ucr->cur_clk = card_clock;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_switch_clock);
+
+int rtsx_usb_card_exclusive_check(struct rtsx_ucr *ucr, int card)
+{
+	int ret;
+	u16 val;
+	u16 cd_mask[] = {
+		[RTSX_USB_SD_CARD] = (CD_MASK & ~SD_CD),
+		[RTSX_USB_MS_CARD] = (CD_MASK & ~MS_CD)
+	};
+
+	ret = rtsx_usb_get_card_status(ucr, &val);
+	/*
+	 * If get status fails, return 0 (ok) for the exclusive check
+	 * and let the flow fail at somewhere else.
+	 */
+	if (ret)
+		return 0;
+
+	if (val & cd_mask[card])
+		return -EIO;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rtsx_usb_card_exclusive_check);
+
+static int rtsx_usb_reset_chip(struct rtsx_ucr *ucr)
+{
+	int ret;
+	u8 val;
+
+	rtsx_usb_init_cmd(ucr);
+
+	if (CHECK_PKG(ucr, LQFP48)) {
+		rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, CARD_PWR_CTL,
+				LDO3318_PWR_MASK, LDO_SUSPEND);
+		rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, CARD_PWR_CTL,
+				FORCE_LDO_POWERB, FORCE_LDO_POWERB);
+		rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, CARD_PULL_CTL1,
+				0x30, 0x10);
+		rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, CARD_PULL_CTL5,
+				0x03, 0x01);
+		rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, CARD_PULL_CTL6,
+				0x0C, 0x04);
+	}
+
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, SYS_DUMMY0, NYET_MSAK, NYET_EN);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, CD_DEGLITCH_WIDTH, 0xFF, 0x08);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD,
+			CD_DEGLITCH_EN, XD_CD_DEGLITCH_EN, 0x0);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, SD30_DRIVE_SEL,
+			SD30_DRIVE_MASK, DRIVER_TYPE_D);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD,
+			CARD_DRIVE_SEL, SD20_DRIVE_MASK, 0x0);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, LDO_POWER_CFG, 0xE0, 0x0);
+
+	if (ucr->is_rts5179)
+		rtsx_usb_add_cmd(ucr, WRITE_REG_CMD,
+				CARD_PULL_CTL5, 0x03, 0x01);
+
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, CARD_DMA1_CTL,
+		       EXTEND_DMA1_ASYNC_SIGNAL, EXTEND_DMA1_ASYNC_SIGNAL);
+	rtsx_usb_add_cmd(ucr, WRITE_REG_CMD, CARD_INT_PEND,
+			XD_INT | MS_INT | SD_INT,
+			XD_INT | MS_INT | SD_INT);
+
+	ret = rtsx_usb_send_cmd(ucr, MODE_C, 100);
+	if (ret)
+		return ret;
+
+	/* config non-crystal mode */
+	rtsx_usb_read_register(ucr, CFG_MODE, &val);
+	if ((val & XTAL_FREE) || ((val & CLK_MODE_MASK) == CLK_MODE_NON_XTAL)) {
+		ret = rtsx_usb_write_phy_register(ucr, 0xC2, 0x7C);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int rtsx_usb_init_chip(struct rtsx_ucr *ucr)
+{
+	int ret;
+	u8 val;
+
+	rtsx_usb_clear_fsm_err(ucr);
+
+	/* power on SSC */
+	ret = rtsx_usb_write_register(ucr,
+			FPDCTL, SSC_POWER_MASK, SSC_POWER_ON);
+	if (ret)
+		return ret;
+
+	usleep_range(100, 1000);
+	ret = rtsx_usb_write_register(ucr, CLK_DIV, CLK_CHANGE, 0x00);
+	if (ret)
+		return ret;
+
+	/* determine IC version */
+	ret = rtsx_usb_read_register(ucr, HW_VERSION, &val);
+	if (ret)
+		return ret;
+
+	ucr->ic_version = val & HW_VER_MASK;
+
+	/* determine package */
+	ret = rtsx_usb_read_register(ucr, CARD_SHARE_MODE, &val);
+	if (ret)
+		return ret;
+
+	if (val & CARD_SHARE_LQFP_SEL) {
+		ucr->package = LQFP48;
+		dev_dbg(&ucr->pusb_intf->dev, "Package: LQFP48\n");
+	} else {
+		ucr->package = QFN24;
+		dev_dbg(&ucr->pusb_intf->dev, "Package: QFN24\n");
+	}
+
+	/* determine IC variations */
+	rtsx_usb_read_register(ucr, CFG_MODE_1, &val);
+	if (val & RTS5179) {
+		ucr->is_rts5179 = true;
+		dev_dbg(&ucr->pusb_intf->dev, "Device is rts5179\n");
+	} else {
+		ucr->is_rts5179 = false;
+	}
+
+	return rtsx_usb_reset_chip(ucr);
+}
+
+static int rtsx_usb_probe(struct usb_interface *intf,
+			 const struct usb_device_id *id)
+{
+	struct usb_device *usb_dev = interface_to_usbdev(intf);
+	struct rtsx_ucr *ucr;
+	int ret;
+
+	dev_dbg(&intf->dev,
+		": Realtek USB Card Reader found at bus %03d address %03d\n",
+		 usb_dev->bus->busnum, usb_dev->devnum);
+
+	ucr = devm_kzalloc(&intf->dev, sizeof(*ucr), GFP_KERNEL);
+	if (!ucr)
+		return -ENOMEM;
+
+	ucr->pusb_dev = usb_dev;
+
+	ucr->iobuf = usb_alloc_coherent(ucr->pusb_dev, IOBUF_SIZE,
+			GFP_KERNEL, &ucr->iobuf_dma);
+	if (!ucr->iobuf)
+		return -ENOMEM;
+
+	usb_set_intfdata(intf, ucr);
+
+	ucr->vendor_id = id->idVendor;
+	ucr->product_id = id->idProduct;
+	ucr->cmd_buf = ucr->rsp_buf = ucr->iobuf;
+
+	mutex_init(&ucr->dev_mutex);
+
+	ucr->pusb_intf = intf;
+
+	/* initialize */
+	ret = rtsx_usb_init_chip(ucr);
+	if (ret)
+		goto out_init_fail;
+
+	ret = mfd_add_devices(&intf->dev, usb_dev->devnum, rtsx_usb_cells,
+			ARRAY_SIZE(rtsx_usb_cells), NULL, 0, NULL);
+	if (ret)
+		goto out_init_fail;
+
+	/* initialize USB SG transfer timer */
+	init_timer(&ucr->sg_timer);
+	setup_timer(&ucr->sg_timer, rtsx_usb_sg_timed_out, (unsigned long) ucr);
+#ifdef CONFIG_PM
+	intf->needs_remote_wakeup = 1;
+	usb_enable_autosuspend(usb_dev);
+#endif
+
+	return 0;
+
+out_init_fail:
+	usb_free_coherent(ucr->pusb_dev, IOBUF_SIZE, ucr->iobuf,
+			ucr->iobuf_dma);
+	return ret;
+}
+
+static void rtsx_usb_disconnect(struct usb_interface *intf)
+{
+	struct rtsx_ucr *ucr = (struct rtsx_ucr *)usb_get_intfdata(intf);
+
+	dev_dbg(&intf->dev, "%s called\n", __func__);
+
+	mfd_remove_devices(&intf->dev);
+
+	usb_set_intfdata(ucr->pusb_intf, NULL);
+	usb_free_coherent(ucr->pusb_dev, IOBUF_SIZE, ucr->iobuf,
+			ucr->iobuf_dma);
+}
+
+#ifdef CONFIG_PM
+static int rtsx_usb_suspend(struct usb_interface *intf, pm_message_t message)
+{
+	struct rtsx_ucr *ucr =
+		(struct rtsx_ucr *)usb_get_intfdata(intf);
+
+	dev_dbg(&intf->dev, "%s called with pm message 0x%04u\n",
+			__func__, message.event);
+
+	mutex_lock(&ucr->dev_mutex);
+	rtsx_usb_turn_off_led(ucr);
+	mutex_unlock(&ucr->dev_mutex);
+	return 0;
+}
+
+static int rtsx_usb_resume(struct usb_interface *intf)
+{
+	return 0;
+}
+
+static int rtsx_usb_reset_resume(struct usb_interface *intf)
+{
+	struct rtsx_ucr *ucr =
+		(struct rtsx_ucr *)usb_get_intfdata(intf);
+
+	rtsx_usb_reset_chip(ucr);
+	return 0;
+}
+
+#else /* CONFIG_PM */
+
+#define rtsx_usb_suspend NULL
+#define rtsx_usb_resume NULL
+#define rtsx_usb_reset_resume NULL
+
+#endif /* CONFIG_PM */
+
+
+static int rtsx_usb_pre_reset(struct usb_interface *intf)
+{
+	struct rtsx_ucr *ucr = (struct rtsx_ucr *)usb_get_intfdata(intf);
+
+	mutex_lock(&ucr->dev_mutex);
+	return 0;
+}
+
+static int rtsx_usb_post_reset(struct usb_interface *intf)
+{
+	struct rtsx_ucr *ucr = (struct rtsx_ucr *)usb_get_intfdata(intf);
+
+	mutex_unlock(&ucr->dev_mutex);
+	return 0;
+}
+
+static struct usb_device_id rtsx_usb_usb_ids[] = {
+	{ USB_DEVICE(0x0BDA, 0x0129) },
+	{ USB_DEVICE(0x0BDA, 0x0139) },
+	{ USB_DEVICE(0x0BDA, 0x0140) },
+	{ }
+};
+
+static struct usb_driver rtsx_usb_driver = {
+	.name			= "rtsx_usb",
+	.probe			= rtsx_usb_probe,
+	.disconnect		= rtsx_usb_disconnect,
+	.suspend		= rtsx_usb_suspend,
+	.resume			= rtsx_usb_resume,
+	.reset_resume		= rtsx_usb_reset_resume,
+	.pre_reset		= rtsx_usb_pre_reset,
+	.post_reset		= rtsx_usb_post_reset,
+	.id_table		= rtsx_usb_usb_ids,
+	.supports_autosuspend	= 1,
+	.soft_unbind		= 1,
+};
+
+module_usb_driver(rtsx_usb_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Roger Tseng <rogerable@realtek.com>");
+MODULE_DESCRIPTION("Realtek USB Card Reader Driver");