flexcan.c 35.1 KB
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/*
 * flexcan.c - FLEXCAN CAN controller driver
 *
 * Copyright (c) 2005-2006 Varma Electronics Oy
 * Copyright (c) 2009 Sascha Hauer, Pengutronix
 * Copyright (c) 2010 Marc Kleine-Budde, Pengutronix
 *
 * Based on code originally by Andrey Volkov <avolkov@varma-el.com>
 *
 * LICENCE:
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * 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.
 *
 */

#include <linux/netdevice.h>
#include <linux/can.h>
#include <linux/can/dev.h>
#include <linux/can/error.h>
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#include <linux/can/led.h>
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#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/of_device.h>
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#include <linux/platform_device.h>
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#include <linux/regulator/consumer.h>
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#define DRV_NAME			"flexcan"

/* 8 for RX fifo and 2 error handling */
#define FLEXCAN_NAPI_WEIGHT		(8 + 2)

/* FLEXCAN module configuration register (CANMCR) bits */
#define FLEXCAN_MCR_MDIS		BIT(31)
#define FLEXCAN_MCR_FRZ			BIT(30)
#define FLEXCAN_MCR_FEN			BIT(29)
#define FLEXCAN_MCR_HALT		BIT(28)
#define FLEXCAN_MCR_NOT_RDY		BIT(27)
#define FLEXCAN_MCR_WAK_MSK		BIT(26)
#define FLEXCAN_MCR_SOFTRST		BIT(25)
#define FLEXCAN_MCR_FRZ_ACK		BIT(24)
#define FLEXCAN_MCR_SUPV		BIT(23)
#define FLEXCAN_MCR_SLF_WAK		BIT(22)
#define FLEXCAN_MCR_WRN_EN		BIT(21)
#define FLEXCAN_MCR_LPM_ACK		BIT(20)
#define FLEXCAN_MCR_WAK_SRC		BIT(19)
#define FLEXCAN_MCR_DOZE		BIT(18)
#define FLEXCAN_MCR_SRX_DIS		BIT(17)
#define FLEXCAN_MCR_BCC			BIT(16)
#define FLEXCAN_MCR_LPRIO_EN		BIT(13)
#define FLEXCAN_MCR_AEN			BIT(12)
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#define FLEXCAN_MCR_MAXMB(x)		((x) & 0x7f)
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#define FLEXCAN_MCR_IDAM_A		(0 << 8)
#define FLEXCAN_MCR_IDAM_B		(1 << 8)
#define FLEXCAN_MCR_IDAM_C		(2 << 8)
#define FLEXCAN_MCR_IDAM_D		(3 << 8)

/* FLEXCAN control register (CANCTRL) bits */
#define FLEXCAN_CTRL_PRESDIV(x)		(((x) & 0xff) << 24)
#define FLEXCAN_CTRL_RJW(x)		(((x) & 0x03) << 22)
#define FLEXCAN_CTRL_PSEG1(x)		(((x) & 0x07) << 19)
#define FLEXCAN_CTRL_PSEG2(x)		(((x) & 0x07) << 16)
#define FLEXCAN_CTRL_BOFF_MSK		BIT(15)
#define FLEXCAN_CTRL_ERR_MSK		BIT(14)
#define FLEXCAN_CTRL_CLK_SRC		BIT(13)
#define FLEXCAN_CTRL_LPB		BIT(12)
#define FLEXCAN_CTRL_TWRN_MSK		BIT(11)
#define FLEXCAN_CTRL_RWRN_MSK		BIT(10)
#define FLEXCAN_CTRL_SMP		BIT(7)
#define FLEXCAN_CTRL_BOFF_REC		BIT(6)
#define FLEXCAN_CTRL_TSYN		BIT(5)
#define FLEXCAN_CTRL_LBUF		BIT(4)
#define FLEXCAN_CTRL_LOM		BIT(3)
#define FLEXCAN_CTRL_PROPSEG(x)		((x) & 0x07)
#define FLEXCAN_CTRL_ERR_BUS		(FLEXCAN_CTRL_ERR_MSK)
#define FLEXCAN_CTRL_ERR_STATE \
	(FLEXCAN_CTRL_TWRN_MSK | FLEXCAN_CTRL_RWRN_MSK | \
	 FLEXCAN_CTRL_BOFF_MSK)
#define FLEXCAN_CTRL_ERR_ALL \
	(FLEXCAN_CTRL_ERR_BUS | FLEXCAN_CTRL_ERR_STATE)

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/* FLEXCAN control register 2 (CTRL2) bits */
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#define FLEXCAN_CTRL2_ECRWRE		BIT(29)
#define FLEXCAN_CTRL2_WRMFRZ		BIT(28)
#define FLEXCAN_CTRL2_RFFN(x)		(((x) & 0x0f) << 24)
#define FLEXCAN_CTRL2_TASD(x)		(((x) & 0x1f) << 19)
#define FLEXCAN_CTRL2_MRP		BIT(18)
#define FLEXCAN_CTRL2_RRS		BIT(17)
#define FLEXCAN_CTRL2_EACEN		BIT(16)
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/* FLEXCAN memory error control register (MECR) bits */
#define FLEXCAN_MECR_ECRWRDIS		BIT(31)
#define FLEXCAN_MECR_HANCEI_MSK		BIT(19)
#define FLEXCAN_MECR_FANCEI_MSK		BIT(18)
#define FLEXCAN_MECR_CEI_MSK		BIT(16)
#define FLEXCAN_MECR_HAERRIE		BIT(15)
#define FLEXCAN_MECR_FAERRIE		BIT(14)
#define FLEXCAN_MECR_EXTERRIE		BIT(13)
#define FLEXCAN_MECR_RERRDIS		BIT(9)
#define FLEXCAN_MECR_ECCDIS		BIT(8)
#define FLEXCAN_MECR_NCEFAFRZ		BIT(7)

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/* FLEXCAN error and status register (ESR) bits */
#define FLEXCAN_ESR_TWRN_INT		BIT(17)
#define FLEXCAN_ESR_RWRN_INT		BIT(16)
#define FLEXCAN_ESR_BIT1_ERR		BIT(15)
#define FLEXCAN_ESR_BIT0_ERR		BIT(14)
#define FLEXCAN_ESR_ACK_ERR		BIT(13)
#define FLEXCAN_ESR_CRC_ERR		BIT(12)
#define FLEXCAN_ESR_FRM_ERR		BIT(11)
#define FLEXCAN_ESR_STF_ERR		BIT(10)
#define FLEXCAN_ESR_TX_WRN		BIT(9)
#define FLEXCAN_ESR_RX_WRN		BIT(8)
#define FLEXCAN_ESR_IDLE		BIT(7)
#define FLEXCAN_ESR_TXRX		BIT(6)
#define FLEXCAN_EST_FLT_CONF_SHIFT	(4)
#define FLEXCAN_ESR_FLT_CONF_MASK	(0x3 << FLEXCAN_EST_FLT_CONF_SHIFT)
#define FLEXCAN_ESR_FLT_CONF_ACTIVE	(0x0 << FLEXCAN_EST_FLT_CONF_SHIFT)
#define FLEXCAN_ESR_FLT_CONF_PASSIVE	(0x1 << FLEXCAN_EST_FLT_CONF_SHIFT)
#define FLEXCAN_ESR_BOFF_INT		BIT(2)
#define FLEXCAN_ESR_ERR_INT		BIT(1)
#define FLEXCAN_ESR_WAK_INT		BIT(0)
#define FLEXCAN_ESR_ERR_BUS \
	(FLEXCAN_ESR_BIT1_ERR | FLEXCAN_ESR_BIT0_ERR | \
	 FLEXCAN_ESR_ACK_ERR | FLEXCAN_ESR_CRC_ERR | \
	 FLEXCAN_ESR_FRM_ERR | FLEXCAN_ESR_STF_ERR)
#define FLEXCAN_ESR_ERR_STATE \
	(FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | FLEXCAN_ESR_BOFF_INT)
#define FLEXCAN_ESR_ERR_ALL \
	(FLEXCAN_ESR_ERR_BUS | FLEXCAN_ESR_ERR_STATE)
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#define FLEXCAN_ESR_ALL_INT \
	(FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | \
	 FLEXCAN_ESR_BOFF_INT | FLEXCAN_ESR_ERR_INT)
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/* FLEXCAN interrupt flag register (IFLAG) bits */
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/* Errata ERR005829 step7: Reserve first valid MB */
#define FLEXCAN_TX_BUF_RESERVED		8
#define FLEXCAN_TX_BUF_ID		9
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#define FLEXCAN_IFLAG_BUF(x)		BIT(x)
#define FLEXCAN_IFLAG_RX_FIFO_OVERFLOW	BIT(7)
#define FLEXCAN_IFLAG_RX_FIFO_WARN	BIT(6)
#define FLEXCAN_IFLAG_RX_FIFO_AVAILABLE	BIT(5)
#define FLEXCAN_IFLAG_DEFAULT \
	(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW | FLEXCAN_IFLAG_RX_FIFO_AVAILABLE | \
	 FLEXCAN_IFLAG_BUF(FLEXCAN_TX_BUF_ID))

/* FLEXCAN message buffers */
#define FLEXCAN_MB_CNT_CODE(x)		(((x) & 0xf) << 24)
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#define FLEXCAN_MB_CODE_RX_INACTIVE	(0x0 << 24)
#define FLEXCAN_MB_CODE_RX_EMPTY	(0x4 << 24)
#define FLEXCAN_MB_CODE_RX_FULL		(0x2 << 24)
#define FLEXCAN_MB_CODE_RX_OVERRRUN	(0x6 << 24)
#define FLEXCAN_MB_CODE_RX_RANSWER	(0xa << 24)

#define FLEXCAN_MB_CODE_TX_INACTIVE	(0x8 << 24)
#define FLEXCAN_MB_CODE_TX_ABORT	(0x9 << 24)
#define FLEXCAN_MB_CODE_TX_DATA		(0xc << 24)
#define FLEXCAN_MB_CODE_TX_TANSWER	(0xe << 24)

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#define FLEXCAN_MB_CNT_SRR		BIT(22)
#define FLEXCAN_MB_CNT_IDE		BIT(21)
#define FLEXCAN_MB_CNT_RTR		BIT(20)
#define FLEXCAN_MB_CNT_LENGTH(x)	(((x) & 0xf) << 16)
#define FLEXCAN_MB_CNT_TIMESTAMP(x)	((x) & 0xffff)

#define FLEXCAN_MB_CODE_MASK		(0xf0ffffff)

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#define FLEXCAN_TIMEOUT_US             (50)

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/*
 * FLEXCAN hardware feature flags
 *
 * Below is some version info we got:
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 *    SOC   Version   IP-Version  Glitch- [TR]WRN_INT Memory err RTR re-
 *                                Filter? connected?  detection  ception in MB
 *   MX25  FlexCAN2  03.00.00.00     no        no         no        no
 *   MX28  FlexCAN2  03.00.04.00    yes       yes         no        no
 *   MX35  FlexCAN2  03.00.00.00     no        no         no        no
 *   MX53  FlexCAN2  03.00.00.00    yes        no         no        no
 *   MX6s  FlexCAN3  10.00.12.00    yes       yes         no       yes
 *   VF610 FlexCAN3  ?               no       yes        yes       yes?
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 *
 * Some SOCs do not have the RX_WARN & TX_WARN interrupt line connected.
 */
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#define FLEXCAN_HAS_V10_FEATURES	BIT(1) /* For core version >= 10 */
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#define FLEXCAN_HAS_BROKEN_ERR_STATE	BIT(2) /* [TR]WRN_INT not connected */
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#define FLEXCAN_HAS_MECR_FEATURES	BIT(3) /* Memory error detection */
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/* Structure of the message buffer */
struct flexcan_mb {
	u32 can_ctrl;
	u32 can_id;
	u32 data[2];
};

/* Structure of the hardware registers */
struct flexcan_regs {
	u32 mcr;		/* 0x00 */
	u32 ctrl;		/* 0x04 */
	u32 timer;		/* 0x08 */
	u32 _reserved1;		/* 0x0c */
	u32 rxgmask;		/* 0x10 */
	u32 rx14mask;		/* 0x14 */
	u32 rx15mask;		/* 0x18 */
	u32 ecr;		/* 0x1c */
	u32 esr;		/* 0x20 */
	u32 imask2;		/* 0x24 */
	u32 imask1;		/* 0x28 */
	u32 iflag2;		/* 0x2c */
	u32 iflag1;		/* 0x30 */
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	u32 ctrl2;		/* 0x34 */
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	u32 esr2;		/* 0x38 */
	u32 imeur;		/* 0x3c */
	u32 lrfr;		/* 0x40 */
	u32 crcr;		/* 0x44 */
	u32 rxfgmask;		/* 0x48 */
	u32 rxfir;		/* 0x4c */
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	u32 _reserved3[12];	/* 0x50 */
	struct flexcan_mb cantxfg[64];	/* 0x80 */
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	/* FIFO-mode:
	 *			MB
	 * 0x080...0x08f	0	RX message buffer
	 * 0x090...0x0df	1-5	reserverd
	 * 0x0e0...0x0ff	6-7	8 entry ID table
	 *				(mx25, mx28, mx35, mx53)
	 * 0x0e0...0x2df	6-7..37	8..128 entry ID table
	 *			  	size conf'ed via ctrl2::RFFN
	 *				(mx6, vf610)
	 */
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	u32 _reserved4[408];
	u32 mecr;		/* 0xae0 */
	u32 erriar;		/* 0xae4 */
	u32 erridpr;		/* 0xae8 */
	u32 errippr;		/* 0xaec */
	u32 rerrar;		/* 0xaf0 */
	u32 rerrdr;		/* 0xaf4 */
	u32 rerrsynr;		/* 0xaf8 */
	u32 errsr;		/* 0xafc */
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};

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struct flexcan_devtype_data {
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	u32 features;	/* hardware controller features */
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};

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struct flexcan_priv {
	struct can_priv can;
	struct napi_struct napi;

	void __iomem *base;
	u32 reg_esr;
	u32 reg_ctrl_default;

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	struct clk *clk_ipg;
	struct clk *clk_per;
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	struct flexcan_platform_data *pdata;
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	const struct flexcan_devtype_data *devtype_data;
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	struct regulator *reg_xceiver;
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};

static struct flexcan_devtype_data fsl_p1010_devtype_data = {
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	.features = FLEXCAN_HAS_BROKEN_ERR_STATE,
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};
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static struct flexcan_devtype_data fsl_imx28_devtype_data;
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static struct flexcan_devtype_data fsl_imx6q_devtype_data = {
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	.features = FLEXCAN_HAS_V10_FEATURES,
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};
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static struct flexcan_devtype_data fsl_vf610_devtype_data = {
	.features = FLEXCAN_HAS_V10_FEATURES | FLEXCAN_HAS_MECR_FEATURES,
};
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static const struct can_bittiming_const flexcan_bittiming_const = {
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	.name = DRV_NAME,
	.tseg1_min = 4,
	.tseg1_max = 16,
	.tseg2_min = 2,
	.tseg2_max = 8,
	.sjw_max = 4,
	.brp_min = 1,
	.brp_max = 256,
	.brp_inc = 1,
};

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/*
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 * Abstract off the read/write for arm versus ppc. This
 * assumes that PPC uses big-endian registers and everything
 * else uses little-endian registers, independent of CPU
 * endianess.
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 */
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#if defined(CONFIG_PPC)
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static inline u32 flexcan_read(void __iomem *addr)
{
	return in_be32(addr);
}

static inline void flexcan_write(u32 val, void __iomem *addr)
{
	out_be32(addr, val);
}
#else
static inline u32 flexcan_read(void __iomem *addr)
{
	return readl(addr);
}

static inline void flexcan_write(u32 val, void __iomem *addr)
{
	writel(val, addr);
}
#endif

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static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv)
{
	if (!priv->reg_xceiver)
		return 0;

	return regulator_enable(priv->reg_xceiver);
}

static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv)
{
	if (!priv->reg_xceiver)
		return 0;

	return regulator_disable(priv->reg_xceiver);
}

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static inline int flexcan_has_and_handle_berr(const struct flexcan_priv *priv,
					      u32 reg_esr)
{
	return (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
		(reg_esr & FLEXCAN_ESR_ERR_BUS);
}

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static int flexcan_chip_enable(struct flexcan_priv *priv)
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{
	struct flexcan_regs __iomem *regs = priv->base;
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	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
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	u32 reg;

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	reg = flexcan_read(&regs->mcr);
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	reg &= ~FLEXCAN_MCR_MDIS;
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	flexcan_write(reg, &regs->mcr);
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	while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
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		udelay(10);
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	if (flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK)
		return -ETIMEDOUT;

	return 0;
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}

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static int flexcan_chip_disable(struct flexcan_priv *priv)
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{
	struct flexcan_regs __iomem *regs = priv->base;
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	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
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	u32 reg;

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	reg = flexcan_read(&regs->mcr);
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	reg |= FLEXCAN_MCR_MDIS;
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	flexcan_write(reg, &regs->mcr);
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	while (timeout-- && !(flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
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		udelay(10);
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	if (!(flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
		return -ETIMEDOUT;

	return 0;
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}

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static int flexcan_chip_freeze(struct flexcan_priv *priv)
{
	struct flexcan_regs __iomem *regs = priv->base;
	unsigned int timeout = 1000 * 1000 * 10 / priv->can.bittiming.bitrate;
	u32 reg;

	reg = flexcan_read(&regs->mcr);
	reg |= FLEXCAN_MCR_HALT;
	flexcan_write(reg, &regs->mcr);

	while (timeout-- && !(flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
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		udelay(100);
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	if (!(flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
		return -ETIMEDOUT;

	return 0;
}

static int flexcan_chip_unfreeze(struct flexcan_priv *priv)
{
	struct flexcan_regs __iomem *regs = priv->base;
	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
	u32 reg;

	reg = flexcan_read(&regs->mcr);
	reg &= ~FLEXCAN_MCR_HALT;
	flexcan_write(reg, &regs->mcr);

	while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
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		udelay(10);
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	if (flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK)
		return -ETIMEDOUT;

	return 0;
}

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static int flexcan_chip_softreset(struct flexcan_priv *priv)
{
	struct flexcan_regs __iomem *regs = priv->base;
	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;

	flexcan_write(FLEXCAN_MCR_SOFTRST, &regs->mcr);
	while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_SOFTRST))
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		udelay(10);
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	if (flexcan_read(&regs->mcr) & FLEXCAN_MCR_SOFTRST)
		return -ETIMEDOUT;

	return 0;
}

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static int __flexcan_get_berr_counter(const struct net_device *dev,
				      struct can_berr_counter *bec)
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{
	const struct flexcan_priv *priv = netdev_priv(dev);
	struct flexcan_regs __iomem *regs = priv->base;
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	u32 reg = flexcan_read(&regs->ecr);
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	bec->txerr = (reg >> 0) & 0xff;
	bec->rxerr = (reg >> 8) & 0xff;

	return 0;
}

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static int flexcan_get_berr_counter(const struct net_device *dev,
				    struct can_berr_counter *bec)
{
	const struct flexcan_priv *priv = netdev_priv(dev);
	int err;

	err = clk_prepare_enable(priv->clk_ipg);
	if (err)
		return err;

	err = clk_prepare_enable(priv->clk_per);
	if (err)
		goto out_disable_ipg;

	err = __flexcan_get_berr_counter(dev, bec);

	clk_disable_unprepare(priv->clk_per);
 out_disable_ipg:
	clk_disable_unprepare(priv->clk_ipg);

	return err;
}

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static int flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	const struct flexcan_priv *priv = netdev_priv(dev);
	struct flexcan_regs __iomem *regs = priv->base;
	struct can_frame *cf = (struct can_frame *)skb->data;
	u32 can_id;
	u32 ctrl = FLEXCAN_MB_CNT_CODE(0xc) | (cf->can_dlc << 16);

	if (can_dropped_invalid_skb(dev, skb))
		return NETDEV_TX_OK;

	netif_stop_queue(dev);

	if (cf->can_id & CAN_EFF_FLAG) {
		can_id = cf->can_id & CAN_EFF_MASK;
		ctrl |= FLEXCAN_MB_CNT_IDE | FLEXCAN_MB_CNT_SRR;
	} else {
		can_id = (cf->can_id & CAN_SFF_MASK) << 18;
	}

	if (cf->can_id & CAN_RTR_FLAG)
		ctrl |= FLEXCAN_MB_CNT_RTR;

	if (cf->can_dlc > 0) {
		u32 data = be32_to_cpup((__be32 *)&cf->data[0]);
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		flexcan_write(data, &regs->cantxfg[FLEXCAN_TX_BUF_ID].data[0]);
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	}
	if (cf->can_dlc > 3) {
		u32 data = be32_to_cpup((__be32 *)&cf->data[4]);
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		flexcan_write(data, &regs->cantxfg[FLEXCAN_TX_BUF_ID].data[1]);
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	}

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	can_put_echo_skb(skb, dev, 0);

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	flexcan_write(can_id, &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_id);
	flexcan_write(ctrl, &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
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	/* Errata ERR005829 step8:
	 * Write twice INACTIVE(0x8) code to first MB.
	 */
	flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
		      &regs->cantxfg[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
	flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
		      &regs->cantxfg[FLEXCAN_TX_BUF_RESERVED].can_ctrl);

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	return NETDEV_TX_OK;
}

static void do_bus_err(struct net_device *dev,
		       struct can_frame *cf, u32 reg_esr)
{
	struct flexcan_priv *priv = netdev_priv(dev);
	int rx_errors = 0, tx_errors = 0;

	cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;

	if (reg_esr & FLEXCAN_ESR_BIT1_ERR) {
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		netdev_dbg(dev, "BIT1_ERR irq\n");
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		cf->data[2] |= CAN_ERR_PROT_BIT1;
		tx_errors = 1;
	}
	if (reg_esr & FLEXCAN_ESR_BIT0_ERR) {
537
		netdev_dbg(dev, "BIT0_ERR irq\n");
538 539 540 541
		cf->data[2] |= CAN_ERR_PROT_BIT0;
		tx_errors = 1;
	}
	if (reg_esr & FLEXCAN_ESR_ACK_ERR) {
542
		netdev_dbg(dev, "ACK_ERR irq\n");
543 544 545 546 547
		cf->can_id |= CAN_ERR_ACK;
		cf->data[3] |= CAN_ERR_PROT_LOC_ACK;
		tx_errors = 1;
	}
	if (reg_esr & FLEXCAN_ESR_CRC_ERR) {
548
		netdev_dbg(dev, "CRC_ERR irq\n");
549 550 551 552 553
		cf->data[2] |= CAN_ERR_PROT_BIT;
		cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ;
		rx_errors = 1;
	}
	if (reg_esr & FLEXCAN_ESR_FRM_ERR) {
554
		netdev_dbg(dev, "FRM_ERR irq\n");
555 556 557 558
		cf->data[2] |= CAN_ERR_PROT_FORM;
		rx_errors = 1;
	}
	if (reg_esr & FLEXCAN_ESR_STF_ERR) {
559
		netdev_dbg(dev, "STF_ERR irq\n");
560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593
		cf->data[2] |= CAN_ERR_PROT_STUFF;
		rx_errors = 1;
	}

	priv->can.can_stats.bus_error++;
	if (rx_errors)
		dev->stats.rx_errors++;
	if (tx_errors)
		dev->stats.tx_errors++;
}

static int flexcan_poll_bus_err(struct net_device *dev, u32 reg_esr)
{
	struct sk_buff *skb;
	struct can_frame *cf;

	skb = alloc_can_err_skb(dev, &cf);
	if (unlikely(!skb))
		return 0;

	do_bus_err(dev, cf, reg_esr);
	netif_receive_skb(skb);

	dev->stats.rx_packets++;
	dev->stats.rx_bytes += cf->can_dlc;

	return 1;
}

static int flexcan_poll_state(struct net_device *dev, u32 reg_esr)
{
	struct flexcan_priv *priv = netdev_priv(dev);
	struct sk_buff *skb;
	struct can_frame *cf;
594
	enum can_state new_state = 0, rx_state = 0, tx_state = 0;
595
	int flt;
596
	struct can_berr_counter bec;
597 598 599

	flt = reg_esr & FLEXCAN_ESR_FLT_CONF_MASK;
	if (likely(flt == FLEXCAN_ESR_FLT_CONF_ACTIVE)) {
600 601 602 603 604
		tx_state = unlikely(reg_esr & FLEXCAN_ESR_TX_WRN) ?
			   CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
		rx_state = unlikely(reg_esr & FLEXCAN_ESR_RX_WRN) ?
			   CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
		new_state = max(tx_state, rx_state);
605
	} else {
606
		__flexcan_get_berr_counter(dev, &bec);
607 608
		new_state = flt == FLEXCAN_ESR_FLT_CONF_PASSIVE ?
			    CAN_STATE_ERROR_PASSIVE : CAN_STATE_BUS_OFF;
609 610 611
		rx_state = bec.rxerr >= bec.txerr ? new_state : 0;
		tx_state = bec.rxerr <= bec.txerr ? new_state : 0;
	}
612 613 614 615 616 617 618 619 620

	/* state hasn't changed */
	if (likely(new_state == priv->can.state))
		return 0;

	skb = alloc_can_err_skb(dev, &cf);
	if (unlikely(!skb))
		return 0;

621 622 623 624 625
	can_change_state(dev, cf, tx_state, rx_state);

	if (unlikely(new_state == CAN_STATE_BUS_OFF))
		can_bus_off(dev);

626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641
	netif_receive_skb(skb);

	dev->stats.rx_packets++;
	dev->stats.rx_bytes += cf->can_dlc;

	return 1;
}

static void flexcan_read_fifo(const struct net_device *dev,
			      struct can_frame *cf)
{
	const struct flexcan_priv *priv = netdev_priv(dev);
	struct flexcan_regs __iomem *regs = priv->base;
	struct flexcan_mb __iomem *mb = &regs->cantxfg[0];
	u32 reg_ctrl, reg_id;

642 643
	reg_ctrl = flexcan_read(&mb->can_ctrl);
	reg_id = flexcan_read(&mb->can_id);
644 645 646 647 648 649 650 651 652
	if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
		cf->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
	else
		cf->can_id = (reg_id >> 18) & CAN_SFF_MASK;

	if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
		cf->can_id |= CAN_RTR_FLAG;
	cf->can_dlc = get_can_dlc((reg_ctrl >> 16) & 0xf);

653 654
	*(__be32 *)(cf->data + 0) = cpu_to_be32(flexcan_read(&mb->data[0]));
	*(__be32 *)(cf->data + 4) = cpu_to_be32(flexcan_read(&mb->data[1]));
655 656

	/* mark as read */
657 658
	flexcan_write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->iflag1);
	flexcan_read(&regs->timer);
659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678
}

static int flexcan_read_frame(struct net_device *dev)
{
	struct net_device_stats *stats = &dev->stats;
	struct can_frame *cf;
	struct sk_buff *skb;

	skb = alloc_can_skb(dev, &cf);
	if (unlikely(!skb)) {
		stats->rx_dropped++;
		return 0;
	}

	flexcan_read_fifo(dev, cf);
	netif_receive_skb(skb);

	stats->rx_packets++;
	stats->rx_bytes += cf->can_dlc;

679 680
	can_led_event(dev, CAN_LED_EVENT_RX);

681 682 683 684 685 686 687 688 689 690 691 692 693 694 695
	return 1;
}

static int flexcan_poll(struct napi_struct *napi, int quota)
{
	struct net_device *dev = napi->dev;
	const struct flexcan_priv *priv = netdev_priv(dev);
	struct flexcan_regs __iomem *regs = priv->base;
	u32 reg_iflag1, reg_esr;
	int work_done = 0;

	/*
	 * The error bits are cleared on read,
	 * use saved value from irq handler.
	 */
696
	reg_esr = flexcan_read(&regs->esr) | priv->reg_esr;
697 698 699 700 701

	/* handle state changes */
	work_done += flexcan_poll_state(dev, reg_esr);

	/* handle RX-FIFO */
702
	reg_iflag1 = flexcan_read(&regs->iflag1);
703 704 705
	while (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE &&
	       work_done < quota) {
		work_done += flexcan_read_frame(dev);
706
		reg_iflag1 = flexcan_read(&regs->iflag1);
707 708 709 710 711 712 713 714 715
	}

	/* report bus errors */
	if (flexcan_has_and_handle_berr(priv, reg_esr) && work_done < quota)
		work_done += flexcan_poll_bus_err(dev, reg_esr);

	if (work_done < quota) {
		napi_complete(napi);
		/* enable IRQs */
716 717
		flexcan_write(FLEXCAN_IFLAG_DEFAULT, &regs->imask1);
		flexcan_write(priv->reg_ctrl_default, &regs->ctrl);
718 719 720 721 722 723 724 725 726 727 728 729 730
	}

	return work_done;
}

static irqreturn_t flexcan_irq(int irq, void *dev_id)
{
	struct net_device *dev = dev_id;
	struct net_device_stats *stats = &dev->stats;
	struct flexcan_priv *priv = netdev_priv(dev);
	struct flexcan_regs __iomem *regs = priv->base;
	u32 reg_iflag1, reg_esr;

731 732
	reg_iflag1 = flexcan_read(&regs->iflag1);
	reg_esr = flexcan_read(&regs->esr);
733 734 735
	/* ACK all bus error and state change IRQ sources */
	if (reg_esr & FLEXCAN_ESR_ALL_INT)
		flexcan_write(reg_esr & FLEXCAN_ESR_ALL_INT, &regs->esr);
736 737 738 739 740 741 742 743 744 745 746 747 748 749 750

	/*
	 * schedule NAPI in case of:
	 * - rx IRQ
	 * - state change IRQ
	 * - bus error IRQ and bus error reporting is activated
	 */
	if ((reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE) ||
	    (reg_esr & FLEXCAN_ESR_ERR_STATE) ||
	    flexcan_has_and_handle_berr(priv, reg_esr)) {
		/*
		 * The error bits are cleared on read,
		 * save them for later use.
		 */
		priv->reg_esr = reg_esr & FLEXCAN_ESR_ERR_BUS;
751 752 753
		flexcan_write(FLEXCAN_IFLAG_DEFAULT &
			~FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->imask1);
		flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
754 755 756 757 758 759
		       &regs->ctrl);
		napi_schedule(&priv->napi);
	}

	/* FIFO overflow */
	if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_OVERFLOW) {
760
		flexcan_write(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW, &regs->iflag1);
761 762 763 764 765 766
		dev->stats.rx_over_errors++;
		dev->stats.rx_errors++;
	}

	/* transmission complete interrupt */
	if (reg_iflag1 & (1 << FLEXCAN_TX_BUF_ID)) {
767
		stats->tx_bytes += can_get_echo_skb(dev, 0);
768
		stats->tx_packets++;
769
		can_led_event(dev, CAN_LED_EVENT_TX);
770 771 772
		/* after sending a RTR frame mailbox is in RX mode */
		flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
			      &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
773
		flexcan_write((1 << FLEXCAN_TX_BUF_ID), &regs->iflag1);
774 775 776 777 778 779 780 781 782 783 784 785 786
		netif_wake_queue(dev);
	}

	return IRQ_HANDLED;
}

static void flexcan_set_bittiming(struct net_device *dev)
{
	const struct flexcan_priv *priv = netdev_priv(dev);
	const struct can_bittiming *bt = &priv->can.bittiming;
	struct flexcan_regs __iomem *regs = priv->base;
	u32 reg;

787
	reg = flexcan_read(&regs->ctrl);
788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809
	reg &= ~(FLEXCAN_CTRL_PRESDIV(0xff) |
		 FLEXCAN_CTRL_RJW(0x3) |
		 FLEXCAN_CTRL_PSEG1(0x7) |
		 FLEXCAN_CTRL_PSEG2(0x7) |
		 FLEXCAN_CTRL_PROPSEG(0x7) |
		 FLEXCAN_CTRL_LPB |
		 FLEXCAN_CTRL_SMP |
		 FLEXCAN_CTRL_LOM);

	reg |= FLEXCAN_CTRL_PRESDIV(bt->brp - 1) |
		FLEXCAN_CTRL_PSEG1(bt->phase_seg1 - 1) |
		FLEXCAN_CTRL_PSEG2(bt->phase_seg2 - 1) |
		FLEXCAN_CTRL_RJW(bt->sjw - 1) |
		FLEXCAN_CTRL_PROPSEG(bt->prop_seg - 1);

	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
		reg |= FLEXCAN_CTRL_LPB;
	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
		reg |= FLEXCAN_CTRL_LOM;
	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
		reg |= FLEXCAN_CTRL_SMP;

810
	netdev_info(dev, "writing ctrl=0x%08x\n", reg);
811
	flexcan_write(reg, &regs->ctrl);
812 813

	/* print chip status */
814 815
	netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x\n", __func__,
		   flexcan_read(&regs->mcr), flexcan_read(&regs->ctrl));
816 817 818 819 820 821 822 823 824 825 826 827
}

/*
 * flexcan_chip_start
 *
 * this functions is entered with clocks enabled
 *
 */
static int flexcan_chip_start(struct net_device *dev)
{
	struct flexcan_priv *priv = netdev_priv(dev);
	struct flexcan_regs __iomem *regs = priv->base;
828
	u32 reg_mcr, reg_ctrl, reg_ctrl2, reg_mecr;
829
	int err, i;
830 831

	/* enable module */
832 833 834
	err = flexcan_chip_enable(priv);
	if (err)
		return err;
835 836

	/* soft reset */
837 838
	err = flexcan_chip_softreset(priv);
	if (err)
839
		goto out_chip_disable;
840 841 842 843 844 845 846 847 848 849 850 851

	flexcan_set_bittiming(dev);

	/*
	 * MCR
	 *
	 * enable freeze
	 * enable fifo
	 * halt now
	 * only supervisor access
	 * enable warning int
	 * choose format C
852
	 * disable local echo
853 854
	 *
	 */
855
	reg_mcr = flexcan_read(&regs->mcr);
856
	reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
857 858
	reg_mcr |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_FEN | FLEXCAN_MCR_HALT |
		FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN |
859 860
		FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_SRX_DIS |
		FLEXCAN_MCR_MAXMB(FLEXCAN_TX_BUF_ID);
861
	netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
862
	flexcan_write(reg_mcr, &regs->mcr);
863 864 865 866 867 868 869 870 871 872 873 874 875

	/*
	 * CTRL
	 *
	 * disable timer sync feature
	 *
	 * disable auto busoff recovery
	 * transmit lowest buffer first
	 *
	 * enable tx and rx warning interrupt
	 * enable bus off interrupt
	 * (== FLEXCAN_CTRL_ERR_STATE)
	 */
876
	reg_ctrl = flexcan_read(&regs->ctrl);
877 878
	reg_ctrl &= ~FLEXCAN_CTRL_TSYN;
	reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF |
879 880 881 882 883 884 885 886 887
		FLEXCAN_CTRL_ERR_STATE;
	/*
	 * enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK),
	 * on most Flexcan cores, too. Otherwise we don't get
	 * any error warning or passive interrupts.
	 */
	if (priv->devtype_data->features & FLEXCAN_HAS_BROKEN_ERR_STATE ||
	    priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
		reg_ctrl |= FLEXCAN_CTRL_ERR_MSK;
888 889
	else
		reg_ctrl &= ~FLEXCAN_CTRL_ERR_MSK;
890 891 892

	/* save for later use */
	priv->reg_ctrl_default = reg_ctrl;
893
	netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
894
	flexcan_write(reg_ctrl, &regs->ctrl);
895

896 897 898 899 900 901
	/* clear and invalidate all mailboxes first */
	for (i = FLEXCAN_TX_BUF_ID; i < ARRAY_SIZE(regs->cantxfg); i++) {
		flexcan_write(FLEXCAN_MB_CODE_RX_INACTIVE,
			      &regs->cantxfg[i].can_ctrl);
	}

902 903 904 905
	/* Errata ERR005829: mark first TX mailbox as INACTIVE */
	flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
		      &regs->cantxfg[FLEXCAN_TX_BUF_RESERVED].can_ctrl);

906 907
	/* mark TX mailbox as INACTIVE */
	flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
908 909
		      &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);

910
	/* acceptance mask/acceptance code (accept everything) */
911 912 913
	flexcan_write(0x0, &regs->rxgmask);
	flexcan_write(0x0, &regs->rx14mask);
	flexcan_write(0x0, &regs->rx15mask);
914

915
	if (priv->devtype_data->features & FLEXCAN_HAS_V10_FEATURES)
916 917
		flexcan_write(0x0, &regs->rxfgmask);

918 919 920 921 922 923 924 925 926 927 928 929 930
	/*
	 * On Vybrid, disable memory error detection interrupts
	 * and freeze mode.
	 * This also works around errata e5295 which generates
	 * false positive memory errors and put the device in
	 * freeze mode.
	 */
	if (priv->devtype_data->features & FLEXCAN_HAS_MECR_FEATURES) {
		/*
		 * Follow the protocol as described in "Detection
		 * and Correction of Memory Errors" to write to
		 * MECR register
		 */
931 932 933
		reg_ctrl2 = flexcan_read(&regs->ctrl2);
		reg_ctrl2 |= FLEXCAN_CTRL2_ECRWRE;
		flexcan_write(reg_ctrl2, &regs->ctrl2);
934 935 936 937 938 939 940 941 942

		reg_mecr = flexcan_read(&regs->mecr);
		reg_mecr &= ~FLEXCAN_MECR_ECRWRDIS;
		flexcan_write(reg_mecr, &regs->mecr);
		reg_mecr &= ~(FLEXCAN_MECR_NCEFAFRZ | FLEXCAN_MECR_HANCEI_MSK |
				FLEXCAN_MECR_FANCEI_MSK);
		flexcan_write(reg_mecr, &regs->mecr);
	}

943 944
	err = flexcan_transceiver_enable(priv);
	if (err)
945
		goto out_chip_disable;
946 947

	/* synchronize with the can bus */
948 949 950
	err = flexcan_chip_unfreeze(priv);
	if (err)
		goto out_transceiver_disable;
951 952 953 954

	priv->can.state = CAN_STATE_ERROR_ACTIVE;

	/* enable FIFO interrupts */
955
	flexcan_write(FLEXCAN_IFLAG_DEFAULT, &regs->imask1);
956 957

	/* print chip status */
958 959
	netdev_dbg(dev, "%s: reading mcr=0x%08x ctrl=0x%08x\n", __func__,
		   flexcan_read(&regs->mcr), flexcan_read(&regs->ctrl));
960 961 962

	return 0;

963 964 965
 out_transceiver_disable:
	flexcan_transceiver_disable(priv);
 out_chip_disable:
966 967 968 969 970 971 972 973 974 975 976 977 978 979 980
	flexcan_chip_disable(priv);
	return err;
}

/*
 * flexcan_chip_stop
 *
 * this functions is entered with clocks enabled
 *
 */
static void flexcan_chip_stop(struct net_device *dev)
{
	struct flexcan_priv *priv = netdev_priv(dev);
	struct flexcan_regs __iomem *regs = priv->base;

981 982 983
	/* freeze + disable module */
	flexcan_chip_freeze(priv);
	flexcan_chip_disable(priv);
984

985 986 987 988 989
	/* Disable all interrupts */
	flexcan_write(0, &regs->imask1);
	flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
		      &regs->ctrl);

990
	flexcan_transceiver_disable(priv);
991 992 993 994 995 996 997 998 999 1000
	priv->can.state = CAN_STATE_STOPPED;

	return;
}

static int flexcan_open(struct net_device *dev)
{
	struct flexcan_priv *priv = netdev_priv(dev);
	int err;

1001 1002 1003 1004 1005 1006 1007
	err = clk_prepare_enable(priv->clk_ipg);
	if (err)
		return err;

	err = clk_prepare_enable(priv->clk_per);
	if (err)
		goto out_disable_ipg;
1008 1009 1010

	err = open_candev(dev);
	if (err)
1011
		goto out_disable_per;
1012 1013 1014 1015 1016 1017 1018 1019

	err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
	if (err)
		goto out_close;

	/* start chip and queuing */
	err = flexcan_chip_start(dev);
	if (err)
1020
		goto out_free_irq;
1021 1022 1023

	can_led_event(dev, CAN_LED_EVENT_OPEN);

1024 1025 1026 1027 1028
	napi_enable(&priv->napi);
	netif_start_queue(dev);

	return 0;

1029 1030
 out_free_irq:
	free_irq(dev->irq, dev);
1031 1032
 out_close:
	close_candev(dev);
1033
 out_disable_per:
1034
	clk_disable_unprepare(priv->clk_per);
1035
 out_disable_ipg:
1036
	clk_disable_unprepare(priv->clk_ipg);
1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049

	return err;
}

static int flexcan_close(struct net_device *dev)
{
	struct flexcan_priv *priv = netdev_priv(dev);

	netif_stop_queue(dev);
	napi_disable(&priv->napi);
	flexcan_chip_stop(dev);

	free_irq(dev->irq, dev);
1050 1051
	clk_disable_unprepare(priv->clk_per);
	clk_disable_unprepare(priv->clk_ipg);
1052 1053 1054

	close_candev(dev);

1055 1056
	can_led_event(dev, CAN_LED_EVENT_STOP);

1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083
	return 0;
}

static int flexcan_set_mode(struct net_device *dev, enum can_mode mode)
{
	int err;

	switch (mode) {
	case CAN_MODE_START:
		err = flexcan_chip_start(dev);
		if (err)
			return err;

		netif_wake_queue(dev);
		break;

	default:
		return -EOPNOTSUPP;
	}

	return 0;
}

static const struct net_device_ops flexcan_netdev_ops = {
	.ndo_open	= flexcan_open,
	.ndo_stop	= flexcan_close,
	.ndo_start_xmit	= flexcan_start_xmit,
1084
	.ndo_change_mtu = can_change_mtu,
1085 1086
};

B
Bill Pemberton 已提交
1087
static int register_flexcandev(struct net_device *dev)
1088 1089 1090 1091 1092
{
	struct flexcan_priv *priv = netdev_priv(dev);
	struct flexcan_regs __iomem *regs = priv->base;
	u32 reg, err;

1093 1094 1095 1096 1097 1098 1099
	err = clk_prepare_enable(priv->clk_ipg);
	if (err)
		return err;

	err = clk_prepare_enable(priv->clk_per);
	if (err)
		goto out_disable_ipg;
1100 1101

	/* select "bus clock", chip must be disabled */
1102 1103 1104
	err = flexcan_chip_disable(priv);
	if (err)
		goto out_disable_per;
1105
	reg = flexcan_read(&regs->ctrl);
1106
	reg |= FLEXCAN_CTRL_CLK_SRC;
1107
	flexcan_write(reg, &regs->ctrl);
1108

1109 1110 1111
	err = flexcan_chip_enable(priv);
	if (err)
		goto out_chip_disable;
1112 1113

	/* set freeze, halt and activate FIFO, restrict register access */
1114
	reg = flexcan_read(&regs->mcr);
1115 1116
	reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT |
		FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV;
1117
	flexcan_write(reg, &regs->mcr);
1118 1119 1120 1121 1122 1123

	/*
	 * Currently we only support newer versions of this core
	 * featuring a RX FIFO. Older cores found on some Coldfire
	 * derivates are not yet supported.
	 */
1124
	reg = flexcan_read(&regs->mcr);
1125
	if (!(reg & FLEXCAN_MCR_FEN)) {
1126
		netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
1127
		err = -ENODEV;
1128
		goto out_chip_disable;
1129 1130 1131 1132 1133
	}

	err = register_candev(dev);

	/* disable core and turn off clocks */
1134
 out_chip_disable:
1135
	flexcan_chip_disable(priv);
1136
 out_disable_per:
1137
	clk_disable_unprepare(priv->clk_per);
1138
 out_disable_ipg:
1139
	clk_disable_unprepare(priv->clk_ipg);
1140 1141 1142 1143

	return err;
}

B
Bill Pemberton 已提交
1144
static void unregister_flexcandev(struct net_device *dev)
1145 1146 1147 1148
{
	unregister_candev(dev);
}

1149 1150
static const struct of_device_id flexcan_of_match[] = {
	{ .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
1151 1152
	{ .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
	{ .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, },
1153
	{ .compatible = "fsl,vf610-flexcan", .data = &fsl_vf610_devtype_data, },
1154 1155
	{ /* sentinel */ },
};
1156
MODULE_DEVICE_TABLE(of, flexcan_of_match);
1157 1158 1159 1160 1161

static const struct platform_device_id flexcan_id_table[] = {
	{ .name = "flexcan", .driver_data = (kernel_ulong_t)&fsl_p1010_devtype_data, },
	{ /* sentinel */ },
};
1162
MODULE_DEVICE_TABLE(platform, flexcan_id_table);
1163

B
Bill Pemberton 已提交
1164
static int flexcan_probe(struct platform_device *pdev)
1165
{
1166
	const struct of_device_id *of_id;
1167
	const struct flexcan_devtype_data *devtype_data;
1168 1169
	struct net_device *dev;
	struct flexcan_priv *priv;
1170
	struct regulator *reg_xceiver;
1171
	struct resource *mem;
1172
	struct clk *clk_ipg = NULL, *clk_per = NULL;
1173 1174
	void __iomem *base;
	int err, irq;
1175 1176
	u32 clock_freq = 0;

1177 1178 1179 1180 1181 1182
	reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver");
	if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER)
		return -EPROBE_DEFER;
	else if (IS_ERR(reg_xceiver))
		reg_xceiver = NULL;

1183 1184 1185
	if (pdev->dev.of_node)
		of_property_read_u32(pdev->dev.of_node,
						"clock-frequency", &clock_freq);
1186 1187

	if (!clock_freq) {
1188 1189 1190
		clk_ipg = devm_clk_get(&pdev->dev, "ipg");
		if (IS_ERR(clk_ipg)) {
			dev_err(&pdev->dev, "no ipg clock defined\n");
1191
			return PTR_ERR(clk_ipg);
1192 1193 1194 1195 1196
		}

		clk_per = devm_clk_get(&pdev->dev, "per");
		if (IS_ERR(clk_per)) {
			dev_err(&pdev->dev, "no per clock defined\n");
1197
			return PTR_ERR(clk_per);
1198
		}
1199
		clock_freq = clk_get_rate(clk_per);
1200 1201 1202 1203
	}

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	irq = platform_get_irq(pdev, 0);
1204 1205
	if (irq <= 0)
		return -ENODEV;
1206

1207 1208 1209
	base = devm_ioremap_resource(&pdev->dev, mem);
	if (IS_ERR(base))
		return PTR_ERR(base);
1210

1211 1212 1213
	of_id = of_match_device(flexcan_of_match, &pdev->dev);
	if (of_id) {
		devtype_data = of_id->data;
1214
	} else if (platform_get_device_id(pdev)->driver_data) {
1215
		devtype_data = (struct flexcan_devtype_data *)
1216
			platform_get_device_id(pdev)->driver_data;
1217
	} else {
1218
		return -ENODEV;
1219 1220
	}

1221 1222 1223 1224
	dev = alloc_candev(sizeof(struct flexcan_priv), 1);
	if (!dev)
		return -ENOMEM;

1225 1226
	dev->netdev_ops = &flexcan_netdev_ops;
	dev->irq = irq;
1227
	dev->flags |= IFF_ECHO;
1228 1229

	priv = netdev_priv(dev);
1230
	priv->can.clock.freq = clock_freq;
1231 1232 1233 1234 1235 1236 1237
	priv->can.bittiming_const = &flexcan_bittiming_const;
	priv->can.do_set_mode = flexcan_set_mode;
	priv->can.do_get_berr_counter = flexcan_get_berr_counter;
	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
		CAN_CTRLMODE_LISTENONLY	| CAN_CTRLMODE_3_SAMPLES |
		CAN_CTRLMODE_BERR_REPORTING;
	priv->base = base;
1238 1239
	priv->clk_ipg = clk_ipg;
	priv->clk_per = clk_per;
1240
	priv->pdata = dev_get_platdata(&pdev->dev);
1241
	priv->devtype_data = devtype_data;
1242

1243
	priv->reg_xceiver = reg_xceiver;
1244

1245 1246
	netif_napi_add(dev, &priv->napi, flexcan_poll, FLEXCAN_NAPI_WEIGHT);

1247
	platform_set_drvdata(pdev, dev);
1248 1249 1250 1251 1252 1253 1254 1255
	SET_NETDEV_DEV(dev, &pdev->dev);

	err = register_flexcandev(dev);
	if (err) {
		dev_err(&pdev->dev, "registering netdev failed\n");
		goto failed_register;
	}

1256 1257
	devm_can_led_init(dev);

1258 1259 1260 1261 1262 1263 1264 1265 1266 1267
	dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%d)\n",
		 priv->base, dev->irq);

	return 0;

 failed_register:
	free_candev(dev);
	return err;
}

B
Bill Pemberton 已提交
1268
static int flexcan_remove(struct platform_device *pdev)
1269 1270
{
	struct net_device *dev = platform_get_drvdata(pdev);
1271
	struct flexcan_priv *priv = netdev_priv(dev);
1272 1273

	unregister_flexcandev(dev);
1274
	netif_napi_del(&priv->napi);
1275 1276
	free_candev(dev);

1277 1278 1279
	return 0;
}

1280
static int __maybe_unused flexcan_suspend(struct device *device)
E
Eric Bénard 已提交
1281
{
1282
	struct net_device *dev = dev_get_drvdata(device);
E
Eric Bénard 已提交
1283
	struct flexcan_priv *priv = netdev_priv(dev);
1284
	int err;
E
Eric Bénard 已提交
1285

1286 1287 1288
	err = flexcan_chip_disable(priv);
	if (err)
		return err;
E
Eric Bénard 已提交
1289 1290 1291 1292 1293 1294 1295 1296 1297 1298

	if (netif_running(dev)) {
		netif_stop_queue(dev);
		netif_device_detach(dev);
	}
	priv->can.state = CAN_STATE_SLEEPING;

	return 0;
}

1299
static int __maybe_unused flexcan_resume(struct device *device)
E
Eric Bénard 已提交
1300
{
1301
	struct net_device *dev = dev_get_drvdata(device);
E
Eric Bénard 已提交
1302 1303 1304 1305 1306 1307 1308
	struct flexcan_priv *priv = netdev_priv(dev);

	priv->can.state = CAN_STATE_ERROR_ACTIVE;
	if (netif_running(dev)) {
		netif_device_attach(dev);
		netif_start_queue(dev);
	}
1309
	return flexcan_chip_enable(priv);
E
Eric Bénard 已提交
1310
}
1311 1312

static SIMPLE_DEV_PM_OPS(flexcan_pm_ops, flexcan_suspend, flexcan_resume);
E
Eric Bénard 已提交
1313

1314
static struct platform_driver flexcan_driver = {
1315 1316
	.driver = {
		.name = DRV_NAME,
1317
		.pm = &flexcan_pm_ops,
1318 1319
		.of_match_table = flexcan_of_match,
	},
1320
	.probe = flexcan_probe,
B
Bill Pemberton 已提交
1321
	.remove = flexcan_remove,
1322
	.id_table = flexcan_id_table,
1323 1324
};

1325
module_platform_driver(flexcan_driver);
1326 1327 1328 1329 1330

MODULE_AUTHOR("Sascha Hauer <kernel@pengutronix.de>, "
	      "Marc Kleine-Budde <kernel@pengutronix.de>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("CAN port driver for flexcan based chip");