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mirror_ubuntu-kernels/drivers/net/ieee802154/mrf24j40.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Driver for Microchip MRF24J40 802.15.4 Wireless-PAN Networking controller
*
* Copyright (C) 2012 Alan Ott <alan@signal11.us>
* Signal 11 Software
*/
#include <linux/spi/spi.h>
#include <linux/interrupt.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/ieee802154.h>
#include <linux/irq.h>
#include <net/cfg802154.h>
#include <net/mac802154.h>
/* MRF24J40 Short Address Registers */
#define REG_RXMCR 0x00 /* Receive MAC control */
#define BIT_PROMI BIT(0)
#define BIT_ERRPKT BIT(1)
#define BIT_NOACKRSP BIT(5)
#define BIT_PANCOORD BIT(3)
#define REG_PANIDL 0x01 /* PAN ID (low) */
#define REG_PANIDH 0x02 /* PAN ID (high) */
#define REG_SADRL 0x03 /* Short address (low) */
#define REG_SADRH 0x04 /* Short address (high) */
#define REG_EADR0 0x05 /* Long address (low) (high is EADR7) */
#define REG_EADR1 0x06
#define REG_EADR2 0x07
#define REG_EADR3 0x08
#define REG_EADR4 0x09
#define REG_EADR5 0x0A
#define REG_EADR6 0x0B
#define REG_EADR7 0x0C
#define REG_RXFLUSH 0x0D
#define REG_ORDER 0x10
#define REG_TXMCR 0x11 /* Transmit MAC control */
#define TXMCR_MIN_BE_SHIFT 3
#define TXMCR_MIN_BE_MASK 0x18
#define TXMCR_CSMA_RETRIES_SHIFT 0
#define TXMCR_CSMA_RETRIES_MASK 0x07
#define REG_ACKTMOUT 0x12
#define REG_ESLOTG1 0x13
#define REG_SYMTICKL 0x14
#define REG_SYMTICKH 0x15
#define REG_PACON0 0x16 /* Power Amplifier Control */
#define REG_PACON1 0x17 /* Power Amplifier Control */
#define REG_PACON2 0x18 /* Power Amplifier Control */
#define REG_TXBCON0 0x1A
#define REG_TXNCON 0x1B /* Transmit Normal FIFO Control */
#define BIT_TXNTRIG BIT(0)
#define BIT_TXNSECEN BIT(1)
#define BIT_TXNACKREQ BIT(2)
#define REG_TXG1CON 0x1C
#define REG_TXG2CON 0x1D
#define REG_ESLOTG23 0x1E
#define REG_ESLOTG45 0x1F
#define REG_ESLOTG67 0x20
#define REG_TXPEND 0x21
#define REG_WAKECON 0x22
#define REG_FROMOFFSET 0x23
#define REG_TXSTAT 0x24 /* TX MAC Status Register */
#define REG_TXBCON1 0x25
#define REG_GATECLK 0x26
#define REG_TXTIME 0x27
#define REG_HSYMTMRL 0x28
#define REG_HSYMTMRH 0x29
#define REG_SOFTRST 0x2A /* Soft Reset */
#define REG_SECCON0 0x2C
#define REG_SECCON1 0x2D
#define REG_TXSTBL 0x2E /* TX Stabilization */
#define REG_RXSR 0x30
#define REG_INTSTAT 0x31 /* Interrupt Status */
#define BIT_TXNIF BIT(0)
#define BIT_RXIF BIT(3)
#define BIT_SECIF BIT(4)
#define BIT_SECIGNORE BIT(7)
#define REG_INTCON 0x32 /* Interrupt Control */
#define BIT_TXNIE BIT(0)
#define BIT_RXIE BIT(3)
#define BIT_SECIE BIT(4)
#define REG_GPIO 0x33 /* GPIO */
#define REG_TRISGPIO 0x34 /* GPIO direction */
#define REG_SLPACK 0x35
#define REG_RFCTL 0x36 /* RF Control Mode Register */
#define BIT_RFRST BIT(2)
#define REG_SECCR2 0x37
#define REG_BBREG0 0x38
#define REG_BBREG1 0x39 /* Baseband Registers */
#define BIT_RXDECINV BIT(2)
#define REG_BBREG2 0x3A /* */
#define BBREG2_CCA_MODE_SHIFT 6
#define BBREG2_CCA_MODE_MASK 0xc0
#define REG_BBREG3 0x3B
#define REG_BBREG4 0x3C
#define REG_BBREG6 0x3E /* */
#define REG_CCAEDTH 0x3F /* Energy Detection Threshold */
/* MRF24J40 Long Address Registers */
#define REG_RFCON0 0x200 /* RF Control Registers */
#define RFCON0_CH_SHIFT 4
#define RFCON0_CH_MASK 0xf0
#define RFOPT_RECOMMEND 3
#define REG_RFCON1 0x201
#define REG_RFCON2 0x202
#define REG_RFCON3 0x203
#define TXPWRL_MASK 0xc0
#define TXPWRL_SHIFT 6
#define TXPWRL_30 0x3
#define TXPWRL_20 0x2
#define TXPWRL_10 0x1
#define TXPWRL_0 0x0
#define TXPWRS_MASK 0x38
#define TXPWRS_SHIFT 3
#define TXPWRS_6_3 0x7
#define TXPWRS_4_9 0x6
#define TXPWRS_3_7 0x5
#define TXPWRS_2_8 0x4
#define TXPWRS_1_9 0x3
#define TXPWRS_1_2 0x2
#define TXPWRS_0_5 0x1
#define TXPWRS_0 0x0
#define REG_RFCON5 0x205
#define REG_RFCON6 0x206
#define REG_RFCON7 0x207
#define REG_RFCON8 0x208
#define REG_SLPCAL0 0x209
#define REG_SLPCAL1 0x20A
#define REG_SLPCAL2 0x20B
#define REG_RFSTATE 0x20F
#define REG_RSSI 0x210
#define REG_SLPCON0 0x211 /* Sleep Clock Control Registers */
#define BIT_INTEDGE BIT(1)
#define REG_SLPCON1 0x220
#define REG_WAKETIMEL 0x222 /* Wake-up Time Match Value Low */
#define REG_WAKETIMEH 0x223 /* Wake-up Time Match Value High */
#define REG_REMCNTL 0x224
#define REG_REMCNTH 0x225
#define REG_MAINCNT0 0x226
#define REG_MAINCNT1 0x227
#define REG_MAINCNT2 0x228
#define REG_MAINCNT3 0x229
#define REG_TESTMODE 0x22F /* Test mode */
#define REG_ASSOEAR0 0x230
#define REG_ASSOEAR1 0x231
#define REG_ASSOEAR2 0x232
#define REG_ASSOEAR3 0x233
#define REG_ASSOEAR4 0x234
#define REG_ASSOEAR5 0x235
#define REG_ASSOEAR6 0x236
#define REG_ASSOEAR7 0x237
#define REG_ASSOSAR0 0x238
#define REG_ASSOSAR1 0x239
#define REG_UNONCE0 0x240
#define REG_UNONCE1 0x241
#define REG_UNONCE2 0x242
#define REG_UNONCE3 0x243
#define REG_UNONCE4 0x244
#define REG_UNONCE5 0x245
#define REG_UNONCE6 0x246
#define REG_UNONCE7 0x247
#define REG_UNONCE8 0x248
#define REG_UNONCE9 0x249
#define REG_UNONCE10 0x24A
#define REG_UNONCE11 0x24B
#define REG_UNONCE12 0x24C
#define REG_RX_FIFO 0x300 /* Receive FIFO */
/* Device configuration: Only channels 11-26 on page 0 are supported. */
#define MRF24J40_CHAN_MIN 11
#define MRF24J40_CHAN_MAX 26
#define CHANNEL_MASK (((u32)1 << (MRF24J40_CHAN_MAX + 1)) \
- ((u32)1 << MRF24J40_CHAN_MIN))
#define TX_FIFO_SIZE 128 /* From datasheet */
#define RX_FIFO_SIZE 144 /* From datasheet */
#define SET_CHANNEL_DELAY_US 192 /* From datasheet */
enum mrf24j40_modules { MRF24J40, MRF24J40MA, MRF24J40MC };
/* Device Private Data */
struct mrf24j40 {
struct spi_device *spi;
struct ieee802154_hw *hw;
struct regmap *regmap_short;
struct regmap *regmap_long;
/* for writing txfifo */
struct spi_message tx_msg;
u8 tx_hdr_buf[2];
struct spi_transfer tx_hdr_trx;
u8 tx_len_buf[2];
struct spi_transfer tx_len_trx;
struct spi_transfer tx_buf_trx;
struct sk_buff *tx_skb;
/* post transmit message to send frame out */
struct spi_message tx_post_msg;
u8 tx_post_buf[2];
struct spi_transfer tx_post_trx;
/* for protect/unprotect/read length rxfifo */
struct spi_message rx_msg;
u8 rx_buf[3];
struct spi_transfer rx_trx;
/* receive handling */
struct spi_message rx_buf_msg;
u8 rx_addr_buf[2];
struct spi_transfer rx_addr_trx;
u8 rx_lqi_buf[2];
struct spi_transfer rx_lqi_trx;
u8 rx_fifo_buf[RX_FIFO_SIZE];
struct spi_transfer rx_fifo_buf_trx;
/* isr handling for reading intstat */
struct spi_message irq_msg;
u8 irq_buf[2];
struct spi_transfer irq_trx;
};
/* regmap information for short address register access */
#define MRF24J40_SHORT_WRITE 0x01
#define MRF24J40_SHORT_READ 0x00
#define MRF24J40_SHORT_NUMREGS 0x3F
/* regmap information for long address register access */
#define MRF24J40_LONG_ACCESS 0x80
#define MRF24J40_LONG_NUMREGS 0x38F
/* Read/Write SPI Commands for Short and Long Address registers. */
#define MRF24J40_READSHORT(reg) ((reg) << 1)
#define MRF24J40_WRITESHORT(reg) ((reg) << 1 | 1)
#define MRF24J40_READLONG(reg) (1 << 15 | (reg) << 5)
#define MRF24J40_WRITELONG(reg) (1 << 15 | (reg) << 5 | 1 << 4)
/* The datasheet indicates the theoretical maximum for SCK to be 10MHz */
#define MAX_SPI_SPEED_HZ 10000000
#define printdev(X) (&X->spi->dev)
static bool
mrf24j40_short_reg_writeable(struct device *dev, unsigned int reg)
{
switch (reg) {
case REG_RXMCR:
case REG_PANIDL:
case REG_PANIDH:
case REG_SADRL:
case REG_SADRH:
case REG_EADR0:
case REG_EADR1:
case REG_EADR2:
case REG_EADR3:
case REG_EADR4:
case REG_EADR5:
case REG_EADR6:
case REG_EADR7:
case REG_RXFLUSH:
case REG_ORDER:
case REG_TXMCR:
case REG_ACKTMOUT:
case REG_ESLOTG1:
case REG_SYMTICKL:
case REG_SYMTICKH:
case REG_PACON0:
case REG_PACON1:
case REG_PACON2:
case REG_TXBCON0:
case REG_TXNCON:
case REG_TXG1CON:
case REG_TXG2CON:
case REG_ESLOTG23:
case REG_ESLOTG45:
case REG_ESLOTG67:
case REG_TXPEND:
case REG_WAKECON:
case REG_FROMOFFSET:
case REG_TXBCON1:
case REG_GATECLK:
case REG_TXTIME:
case REG_HSYMTMRL:
case REG_HSYMTMRH:
case REG_SOFTRST:
case REG_SECCON0:
case REG_SECCON1:
case REG_TXSTBL:
case REG_RXSR:
case REG_INTCON:
case REG_TRISGPIO:
case REG_GPIO:
case REG_RFCTL:
case REG_SECCR2:
case REG_SLPACK:
case REG_BBREG0:
case REG_BBREG1:
case REG_BBREG2:
case REG_BBREG3:
case REG_BBREG4:
case REG_BBREG6:
case REG_CCAEDTH:
return true;
default:
return false;
}
}
static bool
mrf24j40_short_reg_readable(struct device *dev, unsigned int reg)
{
bool rc;
/* all writeable are also readable */
rc = mrf24j40_short_reg_writeable(dev, reg);
if (rc)
return rc;
/* readonly regs */
switch (reg) {
case REG_TXSTAT:
case REG_INTSTAT:
return true;
default:
return false;
}
}
static bool
mrf24j40_short_reg_volatile(struct device *dev, unsigned int reg)
{
/* can be changed during runtime */
switch (reg) {
case REG_TXSTAT:
case REG_INTSTAT:
case REG_RXFLUSH:
case REG_TXNCON:
case REG_SOFTRST:
case REG_RFCTL:
case REG_TXBCON0:
case REG_TXG1CON:
case REG_TXG2CON:
case REG_TXBCON1:
case REG_SECCON0:
case REG_RXSR:
case REG_SLPACK:
case REG_SECCR2:
case REG_BBREG6:
/* use them in spi_async and regmap so it's volatile */
case REG_BBREG1:
return true;
default:
return false;
}
}
static bool
mrf24j40_short_reg_precious(struct device *dev, unsigned int reg)
{
/* don't clear irq line on read */
switch (reg) {
case REG_INTSTAT:
return true;
default:
return false;
}
}
static const struct regmap_config mrf24j40_short_regmap = {
.name = "mrf24j40_short",
.reg_bits = 7,
.val_bits = 8,
.pad_bits = 1,
.write_flag_mask = MRF24J40_SHORT_WRITE,
.read_flag_mask = MRF24J40_SHORT_READ,
.cache_type = REGCACHE_RBTREE,
.max_register = MRF24J40_SHORT_NUMREGS,
.writeable_reg = mrf24j40_short_reg_writeable,
.readable_reg = mrf24j40_short_reg_readable,
.volatile_reg = mrf24j40_short_reg_volatile,
.precious_reg = mrf24j40_short_reg_precious,
};
static bool
mrf24j40_long_reg_writeable(struct device *dev, unsigned int reg)
{
switch (reg) {
case REG_RFCON0:
case REG_RFCON1:
case REG_RFCON2:
case REG_RFCON3:
case REG_RFCON5:
case REG_RFCON6:
case REG_RFCON7:
case REG_RFCON8:
case REG_SLPCAL2:
case REG_SLPCON0:
case REG_SLPCON1:
case REG_WAKETIMEL:
case REG_WAKETIMEH:
case REG_REMCNTL:
case REG_REMCNTH:
case REG_MAINCNT0:
case REG_MAINCNT1:
case REG_MAINCNT2:
case REG_MAINCNT3:
case REG_TESTMODE:
case REG_ASSOEAR0:
case REG_ASSOEAR1:
case REG_ASSOEAR2:
case REG_ASSOEAR3:
case REG_ASSOEAR4:
case REG_ASSOEAR5:
case REG_ASSOEAR6:
case REG_ASSOEAR7:
case REG_ASSOSAR0:
case REG_ASSOSAR1:
case REG_UNONCE0:
case REG_UNONCE1:
case REG_UNONCE2:
case REG_UNONCE3:
case REG_UNONCE4:
case REG_UNONCE5:
case REG_UNONCE6:
case REG_UNONCE7:
case REG_UNONCE8:
case REG_UNONCE9:
case REG_UNONCE10:
case REG_UNONCE11:
case REG_UNONCE12:
return true;
default:
return false;
}
}
static bool
mrf24j40_long_reg_readable(struct device *dev, unsigned int reg)
{
bool rc;
/* all writeable are also readable */
rc = mrf24j40_long_reg_writeable(dev, reg);
if (rc)
return rc;
/* readonly regs */
switch (reg) {
case REG_SLPCAL0:
case REG_SLPCAL1:
case REG_RFSTATE:
case REG_RSSI:
return true;
default:
return false;
}
}
static bool
mrf24j40_long_reg_volatile(struct device *dev, unsigned int reg)
{
/* can be changed during runtime */
switch (reg) {
case REG_SLPCAL0:
case REG_SLPCAL1:
case REG_SLPCAL2:
case REG_RFSTATE:
case REG_RSSI:
case REG_MAINCNT3:
return true;
default:
return false;
}
}
static const struct regmap_config mrf24j40_long_regmap = {
.name = "mrf24j40_long",
.reg_bits = 11,
.val_bits = 8,
.pad_bits = 5,
.write_flag_mask = MRF24J40_LONG_ACCESS,
.read_flag_mask = MRF24J40_LONG_ACCESS,
.cache_type = REGCACHE_RBTREE,
.max_register = MRF24J40_LONG_NUMREGS,
.writeable_reg = mrf24j40_long_reg_writeable,
.readable_reg = mrf24j40_long_reg_readable,
.volatile_reg = mrf24j40_long_reg_volatile,
};
static int mrf24j40_long_regmap_write(void *context, const void *data,
size_t count)
{
struct spi_device *spi = context;
u8 buf[3];
if (count > 3)
return -EINVAL;
/* regmap supports read/write mask only in frist byte
* long write access need to set the 12th bit, so we
* make special handling for write.
*/
memcpy(buf, data, count);
buf[1] |= (1 << 4);
return spi_write(spi, buf, count);
}
static int
mrf24j40_long_regmap_read(void *context, const void *reg, size_t reg_size,
void *val, size_t val_size)
{
struct spi_device *spi = context;
return spi_write_then_read(spi, reg, reg_size, val, val_size);
}
static const struct regmap_bus mrf24j40_long_regmap_bus = {
.write = mrf24j40_long_regmap_write,
.read = mrf24j40_long_regmap_read,
.reg_format_endian_default = REGMAP_ENDIAN_BIG,
.val_format_endian_default = REGMAP_ENDIAN_BIG,
};
static void write_tx_buf_complete(void *context)
{
struct mrf24j40 *devrec = context;
__le16 fc = ieee802154_get_fc_from_skb(devrec->tx_skb);
u8 val = BIT_TXNTRIG;
int ret;
if (ieee802154_is_secen(fc))
val |= BIT_TXNSECEN;
if (ieee802154_is_ackreq(fc))
val |= BIT_TXNACKREQ;
devrec->tx_post_msg.complete = NULL;
devrec->tx_post_buf[0] = MRF24J40_WRITESHORT(REG_TXNCON);
devrec->tx_post_buf[1] = val;
ret = spi_async(devrec->spi, &devrec->tx_post_msg);
if (ret)
dev_err(printdev(devrec), "SPI write Failed for transmit buf\n");
}
/* This function relies on an undocumented write method. Once a write command
and address is set, as many bytes of data as desired can be clocked into
the device. The datasheet only shows setting one byte at a time. */
static int write_tx_buf(struct mrf24j40 *devrec, u16 reg,
const u8 *data, size_t length)
{
u16 cmd;
int ret;
/* Range check the length. 2 bytes are used for the length fields.*/
if (length > TX_FIFO_SIZE-2) {
dev_err(printdev(devrec), "write_tx_buf() was passed too large a buffer. Performing short write.\n");
length = TX_FIFO_SIZE-2;
}
cmd = MRF24J40_WRITELONG(reg);
devrec->tx_hdr_buf[0] = cmd >> 8 & 0xff;
devrec->tx_hdr_buf[1] = cmd & 0xff;
devrec->tx_len_buf[0] = 0x0; /* Header Length. Set to 0 for now. TODO */
devrec->tx_len_buf[1] = length; /* Total length */
devrec->tx_buf_trx.tx_buf = data;
devrec->tx_buf_trx.len = length;
ret = spi_async(devrec->spi, &devrec->tx_msg);
if (ret)
dev_err(printdev(devrec), "SPI write Failed for TX buf\n");
return ret;
}
static int mrf24j40_tx(struct ieee802154_hw *hw, struct sk_buff *skb)
{
struct mrf24j40 *devrec = hw->priv;
dev_dbg(printdev(devrec), "tx packet of %d bytes\n", skb->len);
devrec->tx_skb = skb;
return write_tx_buf(devrec, 0x000, skb->data, skb->len);
}
static int mrf24j40_ed(struct ieee802154_hw *hw, u8 *level)
{
/* TODO: */
pr_warn("mrf24j40: ed not implemented\n");
*level = 0;
return 0;
}
static int mrf24j40_start(struct ieee802154_hw *hw)
{
struct mrf24j40 *devrec = hw->priv;
dev_dbg(printdev(devrec), "start\n");
/* Clear TXNIE and RXIE. Enable interrupts */
return regmap_update_bits(devrec->regmap_short, REG_INTCON,
BIT_TXNIE | BIT_RXIE | BIT_SECIE, 0);
}
static void mrf24j40_stop(struct ieee802154_hw *hw)
{
struct mrf24j40 *devrec = hw->priv;
dev_dbg(printdev(devrec), "stop\n");
/* Set TXNIE and RXIE. Disable Interrupts */
regmap_update_bits(devrec->regmap_short, REG_INTCON,
BIT_TXNIE | BIT_RXIE, BIT_TXNIE | BIT_RXIE);
}
static int mrf24j40_set_channel(struct ieee802154_hw *hw, u8 page, u8 channel)
{
struct mrf24j40 *devrec = hw->priv;
u8 val;
int ret;
dev_dbg(printdev(devrec), "Set Channel %d\n", channel);
WARN_ON(page != 0);
WARN_ON(channel < MRF24J40_CHAN_MIN);
WARN_ON(channel > MRF24J40_CHAN_MAX);
/* Set Channel TODO */
val = (channel - 11) << RFCON0_CH_SHIFT | RFOPT_RECOMMEND;
ret = regmap_update_bits(devrec->regmap_long, REG_RFCON0,
RFCON0_CH_MASK, val);
if (ret)
return ret;
/* RF Reset */
ret = regmap_update_bits(devrec->regmap_short, REG_RFCTL, BIT_RFRST,
BIT_RFRST);
if (ret)
return ret;
ret = regmap_update_bits(devrec->regmap_short, REG_RFCTL, BIT_RFRST, 0);
if (!ret)
udelay(SET_CHANNEL_DELAY_US); /* per datasheet */
return ret;
}
static int mrf24j40_filter(struct ieee802154_hw *hw,
struct ieee802154_hw_addr_filt *filt,
unsigned long changed)
{
struct mrf24j40 *devrec = hw->priv;
dev_dbg(printdev(devrec), "filter\n");
if (changed & IEEE802154_AFILT_SADDR_CHANGED) {
/* Short Addr */
u8 addrh, addrl;
addrh = le16_to_cpu(filt->short_addr) >> 8 & 0xff;
addrl = le16_to_cpu(filt->short_addr) & 0xff;
regmap_write(devrec->regmap_short, REG_SADRH, addrh);
regmap_write(devrec->regmap_short, REG_SADRL, addrl);
dev_dbg(printdev(devrec),
"Set short addr to %04hx\n", filt->short_addr);
}
if (changed & IEEE802154_AFILT_IEEEADDR_CHANGED) {
/* Device Address */
u8 i, addr[8];
memcpy(addr, &filt->ieee_addr, 8);
for (i = 0; i < 8; i++)
regmap_write(devrec->regmap_short, REG_EADR0 + i,
addr[i]);
#ifdef DEBUG
pr_debug("Set long addr to: ");
for (i = 0; i < 8; i++)
pr_debug("%02hhx ", addr[7 - i]);
pr_debug("\n");
#endif
}
if (changed & IEEE802154_AFILT_PANID_CHANGED) {
/* PAN ID */
u8 panidl, panidh;
panidh = le16_to_cpu(filt->pan_id) >> 8 & 0xff;
panidl = le16_to_cpu(filt->pan_id) & 0xff;
regmap_write(devrec->regmap_short, REG_PANIDH, panidh);
regmap_write(devrec->regmap_short, REG_PANIDL, panidl);
dev_dbg(printdev(devrec), "Set PANID to %04hx\n", filt->pan_id);
}
if (changed & IEEE802154_AFILT_PANC_CHANGED) {
/* Pan Coordinator */
u8 val;
int ret;
if (filt->pan_coord)
val = BIT_PANCOORD;
else
val = 0;
ret = regmap_update_bits(devrec->regmap_short, REG_RXMCR,
BIT_PANCOORD, val);
if (ret)
return ret;
/* REG_SLOTTED is maintained as default (unslotted/CSMA-CA).
* REG_ORDER is maintained as default (no beacon/superframe).
*/
dev_dbg(printdev(devrec), "Set Pan Coord to %s\n",
filt->pan_coord ? "on" : "off");
}
return 0;
}
static void mrf24j40_handle_rx_read_buf_unlock(struct mrf24j40 *devrec)
{
int ret;
/* Turn back on reception of packets off the air. */
devrec->rx_msg.complete = NULL;
devrec->rx_buf[0] = MRF24J40_WRITESHORT(REG_BBREG1);
devrec->rx_buf[1] = 0x00; /* CLR RXDECINV */
ret = spi_async(devrec->spi, &devrec->rx_msg);
if (ret)
dev_err(printdev(devrec), "failed to unlock rx buffer\n");
}
static void mrf24j40_handle_rx_read_buf_complete(void *context)
{
struct mrf24j40 *devrec = context;
u8 len = devrec->rx_buf[2];
u8 rx_local_buf[RX_FIFO_SIZE];
struct sk_buff *skb;
memcpy(rx_local_buf, devrec->rx_fifo_buf, len);
mrf24j40_handle_rx_read_buf_unlock(devrec);
skb = dev_alloc_skb(IEEE802154_MTU);
if (!skb) {
dev_err(printdev(devrec), "failed to allocate skb\n");
return;
}
skb_put_data(skb, rx_local_buf, len);
ieee802154_rx_irqsafe(devrec->hw, skb, 0);
#ifdef DEBUG
print_hex_dump(KERN_DEBUG, "mrf24j40 rx: ", DUMP_PREFIX_OFFSET, 16, 1,
rx_local_buf, len, 0);
pr_debug("mrf24j40 rx: lqi: %02hhx rssi: %02hhx\n",
devrec->rx_lqi_buf[0], devrec->rx_lqi_buf[1]);
#endif
}
static void mrf24j40_handle_rx_read_buf(void *context)
{
struct mrf24j40 *devrec = context;
u16 cmd;
int ret;
/* if length is invalid read the full MTU */
if (!ieee802154_is_valid_psdu_len(devrec->rx_buf[2]))
devrec->rx_buf[2] = IEEE802154_MTU;
cmd = MRF24J40_READLONG(REG_RX_FIFO + 1);
devrec->rx_addr_buf[0] = cmd >> 8 & 0xff;
devrec->rx_addr_buf[1] = cmd & 0xff;
devrec->rx_fifo_buf_trx.len = devrec->rx_buf[2];
ret = spi_async(devrec->spi, &devrec->rx_buf_msg);
if (ret) {
dev_err(printdev(devrec), "failed to read rx buffer\n");
mrf24j40_handle_rx_read_buf_unlock(devrec);
}
}
static void mrf24j40_handle_rx_read_len(void *context)
{
struct mrf24j40 *devrec = context;
u16 cmd;
int ret;
/* read the length of received frame */
devrec->rx_msg.complete = mrf24j40_handle_rx_read_buf;
devrec->rx_trx.len = 3;
cmd = MRF24J40_READLONG(REG_RX_FIFO);
devrec->rx_buf[0] = cmd >> 8 & 0xff;
devrec->rx_buf[1] = cmd & 0xff;
ret = spi_async(devrec->spi, &devrec->rx_msg);
if (ret) {
dev_err(printdev(devrec), "failed to read rx buffer length\n");
mrf24j40_handle_rx_read_buf_unlock(devrec);
}
}
static int mrf24j40_handle_rx(struct mrf24j40 *devrec)
{
/* Turn off reception of packets off the air. This prevents the
* device from overwriting the buffer while we're reading it.
*/
devrec->rx_msg.complete = mrf24j40_handle_rx_read_len;
devrec->rx_trx.len = 2;
devrec->rx_buf[0] = MRF24J40_WRITESHORT(REG_BBREG1);
devrec->rx_buf[1] = BIT_RXDECINV; /* SET RXDECINV */
return spi_async(devrec->spi, &devrec->rx_msg);
}
static int
mrf24j40_csma_params(struct ieee802154_hw *hw, u8 min_be, u8 max_be,
u8 retries)
{
struct mrf24j40 *devrec = hw->priv;
u8 val;
/* min_be */
val = min_be << TXMCR_MIN_BE_SHIFT;
/* csma backoffs */
val |= retries << TXMCR_CSMA_RETRIES_SHIFT;
return regmap_update_bits(devrec->regmap_short, REG_TXMCR,
TXMCR_MIN_BE_MASK | TXMCR_CSMA_RETRIES_MASK,
val);
}
static int mrf24j40_set_cca_mode(struct ieee802154_hw *hw,
const struct wpan_phy_cca *cca)
{
struct mrf24j40 *devrec = hw->priv;
u8 val;
/* mapping 802.15.4 to driver spec */
switch (cca->mode) {
case NL802154_CCA_ENERGY:
val = 2;
break;
case NL802154_CCA_CARRIER:
val = 1;
break;
case NL802154_CCA_ENERGY_CARRIER:
switch (cca->opt) {
case NL802154_CCA_OPT_ENERGY_CARRIER_AND:
val = 3;
break;
default:
return -EINVAL;
}
break;
default:
return -EINVAL;
}
return regmap_update_bits(devrec->regmap_short, REG_BBREG2,
BBREG2_CCA_MODE_MASK,
val << BBREG2_CCA_MODE_SHIFT);
}
/* array for representing ed levels */
static const s32 mrf24j40_ed_levels[] = {
-9000, -8900, -8800, -8700, -8600, -8500, -8400, -8300, -8200, -8100,
-8000, -7900, -7800, -7700, -7600, -7500, -7400, -7300, -7200, -7100,
-7000, -6900, -6800, -6700, -6600, -6500, -6400, -6300, -6200, -6100,
-6000, -5900, -5800, -5700, -5600, -5500, -5400, -5300, -5200, -5100,
-5000, -4900, -4800, -4700, -4600, -4500, -4400, -4300, -4200, -4100,
-4000, -3900, -3800, -3700, -3600, -3500
};
/* map ed levels to register value */
static const s32 mrf24j40_ed_levels_map[][2] = {
{ -9000, 0 }, { -8900, 1 }, { -8800, 2 }, { -8700, 5 }, { -8600, 9 },
{ -8500, 13 }, { -8400, 18 }, { -8300, 23 }, { -8200, 27 },
{ -8100, 32 }, { -8000, 37 }, { -7900, 43 }, { -7800, 48 },
{ -7700, 53 }, { -7600, 58 }, { -7500, 63 }, { -7400, 68 },
{ -7300, 73 }, { -7200, 78 }, { -7100, 83 }, { -7000, 89 },
{ -6900, 95 }, { -6800, 100 }, { -6700, 107 }, { -6600, 111 },
{ -6500, 117 }, { -6400, 121 }, { -6300, 125 }, { -6200, 129 },
{ -6100, 133 }, { -6000, 138 }, { -5900, 143 }, { -5800, 148 },
{ -5700, 153 }, { -5600, 159 }, { -5500, 165 }, { -5400, 170 },
{ -5300, 176 }, { -5200, 183 }, { -5100, 188 }, { -5000, 193 },
{ -4900, 198 }, { -4800, 203 }, { -4700, 207 }, { -4600, 212 },
{ -4500, 216 }, { -4400, 221 }, { -4300, 225 }, { -4200, 228 },
{ -4100, 233 }, { -4000, 239 }, { -3900, 245 }, { -3800, 250 },
{ -3700, 253 }, { -3600, 254 }, { -3500, 255 },
};
static int mrf24j40_set_cca_ed_level(struct ieee802154_hw *hw, s32 mbm)
{
struct mrf24j40 *devrec = hw->priv;
int i;
for (i = 0; i < ARRAY_SIZE(mrf24j40_ed_levels_map); i++) {
if (mrf24j40_ed_levels_map[i][0] == mbm)
return regmap_write(devrec->regmap_short, REG_CCAEDTH,
mrf24j40_ed_levels_map[i][1]);
}
return -EINVAL;
}
static const s32 mrf24j40ma_powers[] = {
0, -50, -120, -190, -280, -370, -490, -630, -1000, -1050, -1120, -1190,
-1280, -1370, -1490, -1630, -2000, -2050, -2120, -2190, -2280, -2370,
-2490, -2630, -3000, -3050, -3120, -3190, -3280, -3370, -3490, -3630,
};
static int mrf24j40_set_txpower(struct ieee802154_hw *hw, s32 mbm)
{
struct mrf24j40 *devrec = hw->priv;
s32 small_scale;
u8 val;
if (0 >= mbm && mbm > -1000) {
val = TXPWRL_0 << TXPWRL_SHIFT;
small_scale = mbm;
} else if (-1000 >= mbm && mbm > -2000) {
val = TXPWRL_10 << TXPWRL_SHIFT;
small_scale = mbm + 1000;
} else if (-2000 >= mbm && mbm > -3000) {
val = TXPWRL_20 << TXPWRL_SHIFT;
small_scale = mbm + 2000;
} else if (-3000 >= mbm && mbm > -4000) {
val = TXPWRL_30 << TXPWRL_SHIFT;
small_scale = mbm + 3000;
} else {
return -EINVAL;
}
switch (small_scale) {
case 0:
val |= (TXPWRS_0 << TXPWRS_SHIFT);
break;
case -50:
val |= (TXPWRS_0_5 << TXPWRS_SHIFT);
break;
case -120:
val |= (TXPWRS_1_2 << TXPWRS_SHIFT);
break;
case -190:
val |= (TXPWRS_1_9 << TXPWRS_SHIFT);
break;
case -280:
val |= (TXPWRS_2_8 << TXPWRS_SHIFT);
break;
case -370:
val |= (TXPWRS_3_7 << TXPWRS_SHIFT);
break;
case -490:
val |= (TXPWRS_4_9 << TXPWRS_SHIFT);
break;
case -630:
val |= (TXPWRS_6_3 << TXPWRS_SHIFT);
break;
default:
return -EINVAL;
}
return regmap_update_bits(devrec->regmap_long, REG_RFCON3,
TXPWRL_MASK | TXPWRS_MASK, val);
}
static int mrf24j40_set_promiscuous_mode(struct ieee802154_hw *hw, bool on)
{
struct mrf24j40 *devrec = hw->priv;
int ret;
if (on) {
/* set PROMI, ERRPKT and NOACKRSP */
ret = regmap_update_bits(devrec->regmap_short, REG_RXMCR,
BIT_PROMI | BIT_ERRPKT | BIT_NOACKRSP,
BIT_PROMI | BIT_ERRPKT | BIT_NOACKRSP);
} else {
/* clear PROMI, ERRPKT and NOACKRSP */
ret = regmap_update_bits(devrec->regmap_short, REG_RXMCR,
BIT_PROMI | BIT_ERRPKT | BIT_NOACKRSP,
0);
}
return ret;
}
static const struct ieee802154_ops mrf24j40_ops = {
.owner = THIS_MODULE,
.xmit_async = mrf24j40_tx,
.ed = mrf24j40_ed,
.start = mrf24j40_start,
.stop = mrf24j40_stop,
.set_channel = mrf24j40_set_channel,
.set_hw_addr_filt = mrf24j40_filter,
.set_csma_params = mrf24j40_csma_params,
.set_cca_mode = mrf24j40_set_cca_mode,
.set_cca_ed_level = mrf24j40_set_cca_ed_level,
.set_txpower = mrf24j40_set_txpower,
.set_promiscuous_mode = mrf24j40_set_promiscuous_mode,
};
static void mrf24j40_intstat_complete(void *context)
{
struct mrf24j40 *devrec = context;
u8 intstat = devrec->irq_buf[1];
enable_irq(devrec->spi->irq);
/* Ignore Rx security decryption */
if (intstat & BIT_SECIF)
regmap_write_async(devrec->regmap_short, REG_SECCON0,
BIT_SECIGNORE);
/* Check for TX complete */
if (intstat & BIT_TXNIF)
ieee802154_xmit_complete(devrec->hw, devrec->tx_skb, false);
/* Check for Rx */
if (intstat & BIT_RXIF)
mrf24j40_handle_rx(devrec);
}
static irqreturn_t mrf24j40_isr(int irq, void *data)
{
struct mrf24j40 *devrec = data;
int ret;
disable_irq_nosync(irq);
devrec->irq_buf[0] = MRF24J40_READSHORT(REG_INTSTAT);
devrec->irq_buf[1] = 0;
/* Read the interrupt status */
ret = spi_async(devrec->spi, &devrec->irq_msg);
if (ret) {
enable_irq(irq);
return IRQ_NONE;
}
return IRQ_HANDLED;
}
static int mrf24j40_hw_init(struct mrf24j40 *devrec)
{
u32 irq_type;
int ret;
/* Initialize the device.
From datasheet section 3.2: Initialization. */
ret = regmap_write(devrec->regmap_short, REG_SOFTRST, 0x07);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_short, REG_PACON2, 0x98);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_short, REG_TXSTBL, 0x95);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_long, REG_RFCON0, 0x03);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_long, REG_RFCON1, 0x01);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_long, REG_RFCON2, 0x80);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_long, REG_RFCON6, 0x90);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_long, REG_RFCON7, 0x80);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_long, REG_RFCON8, 0x10);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_long, REG_SLPCON1, 0x21);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_short, REG_BBREG2, 0x80);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_short, REG_CCAEDTH, 0x60);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_short, REG_BBREG6, 0x40);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_short, REG_RFCTL, 0x04);
if (ret)
goto err_ret;
ret = regmap_write(devrec->regmap_short, REG_RFCTL, 0x0);
if (ret)
goto err_ret;
udelay(192);
/* Set RX Mode. RXMCR<1:0>: 0x0 normal, 0x1 promisc, 0x2 error */
ret = regmap_update_bits(devrec->regmap_short, REG_RXMCR, 0x03, 0x00);
if (ret)
goto err_ret;
if (spi_get_device_id(devrec->spi)->driver_data == MRF24J40MC) {
/* Enable external amplifier.
* From MRF24J40MC datasheet section 1.3: Operation.
*/
regmap_update_bits(devrec->regmap_long, REG_TESTMODE, 0x07,
0x07);
/* Set GPIO3 as output. */
regmap_update_bits(devrec->regmap_short, REG_TRISGPIO, 0x08,
0x08);
/* Set GPIO3 HIGH to enable U5 voltage regulator */
regmap_update_bits(devrec->regmap_short, REG_GPIO, 0x08, 0x08);
/* Reduce TX pwr to meet FCC requirements.
* From MRF24J40MC datasheet section 3.1.1
*/
regmap_write(devrec->regmap_long, REG_RFCON3, 0x28);
}
irq_type = irq_get_trigger_type(devrec->spi->irq);
if (irq_type == IRQ_TYPE_EDGE_RISING ||
irq_type == IRQ_TYPE_EDGE_FALLING)
dev_warn(&devrec->spi->dev,
"Using edge triggered irq's are not recommended, because it can cause races and result in a non-functional driver!\n");
switch (irq_type) {
case IRQ_TYPE_EDGE_RISING:
case IRQ_TYPE_LEVEL_HIGH:
/* set interrupt polarity to rising */
ret = regmap_update_bits(devrec->regmap_long, REG_SLPCON0,
BIT_INTEDGE, BIT_INTEDGE);
if (ret)
goto err_ret;
break;
default:
/* default is falling edge */
break;
}
return 0;
err_ret:
return ret;
}
static void
mrf24j40_setup_tx_spi_messages(struct mrf24j40 *devrec)
{
spi_message_init(&devrec->tx_msg);
devrec->tx_msg.context = devrec;
devrec->tx_msg.complete = write_tx_buf_complete;
devrec->tx_hdr_trx.len = 2;
devrec->tx_hdr_trx.tx_buf = devrec->tx_hdr_buf;
spi_message_add_tail(&devrec->tx_hdr_trx, &devrec->tx_msg);
devrec->tx_len_trx.len = 2;
devrec->tx_len_trx.tx_buf = devrec->tx_len_buf;
spi_message_add_tail(&devrec->tx_len_trx, &devrec->tx_msg);
spi_message_add_tail(&devrec->tx_buf_trx, &devrec->tx_msg);
spi_message_init(&devrec->tx_post_msg);
devrec->tx_post_msg.context = devrec;
devrec->tx_post_trx.len = 2;
devrec->tx_post_trx.tx_buf = devrec->tx_post_buf;
spi_message_add_tail(&devrec->tx_post_trx, &devrec->tx_post_msg);
}
static void
mrf24j40_setup_rx_spi_messages(struct mrf24j40 *devrec)
{
spi_message_init(&devrec->rx_msg);
devrec->rx_msg.context = devrec;
devrec->rx_trx.len = 2;
devrec->rx_trx.tx_buf = devrec->rx_buf;
devrec->rx_trx.rx_buf = devrec->rx_buf;
spi_message_add_tail(&devrec->rx_trx, &devrec->rx_msg);
spi_message_init(&devrec->rx_buf_msg);
devrec->rx_buf_msg.context = devrec;
devrec->rx_buf_msg.complete = mrf24j40_handle_rx_read_buf_complete;
devrec->rx_addr_trx.len = 2;
devrec->rx_addr_trx.tx_buf = devrec->rx_addr_buf;
spi_message_add_tail(&devrec->rx_addr_trx, &devrec->rx_buf_msg);
devrec->rx_fifo_buf_trx.rx_buf = devrec->rx_fifo_buf;
spi_message_add_tail(&devrec->rx_fifo_buf_trx, &devrec->rx_buf_msg);
devrec->rx_lqi_trx.len = 2;
devrec->rx_lqi_trx.rx_buf = devrec->rx_lqi_buf;
spi_message_add_tail(&devrec->rx_lqi_trx, &devrec->rx_buf_msg);
}
static void
mrf24j40_setup_irq_spi_messages(struct mrf24j40 *devrec)
{
spi_message_init(&devrec->irq_msg);
devrec->irq_msg.context = devrec;
devrec->irq_msg.complete = mrf24j40_intstat_complete;
devrec->irq_trx.len = 2;
devrec->irq_trx.tx_buf = devrec->irq_buf;
devrec->irq_trx.rx_buf = devrec->irq_buf;
spi_message_add_tail(&devrec->irq_trx, &devrec->irq_msg);
}
static void mrf24j40_phy_setup(struct mrf24j40 *devrec)
{
ieee802154_random_extended_addr(&devrec->hw->phy->perm_extended_addr);
devrec->hw->phy->current_channel = 11;
/* mrf24j40 supports max_minbe 0 - 3 */
devrec->hw->phy->supported.max_minbe = 3;
/* datasheet doesn't say anything about max_be, but we have min_be
* So we assume the max_be default.
*/
devrec->hw->phy->supported.min_maxbe = 5;
devrec->hw->phy->supported.max_maxbe = 5;
devrec->hw->phy->cca.mode = NL802154_CCA_CARRIER;
devrec->hw->phy->supported.cca_modes = BIT(NL802154_CCA_ENERGY) |
BIT(NL802154_CCA_CARRIER) |
BIT(NL802154_CCA_ENERGY_CARRIER);
devrec->hw->phy->supported.cca_opts = BIT(NL802154_CCA_OPT_ENERGY_CARRIER_AND);
devrec->hw->phy->cca_ed_level = -6900;
devrec->hw->phy->supported.cca_ed_levels = mrf24j40_ed_levels;
devrec->hw->phy->supported.cca_ed_levels_size = ARRAY_SIZE(mrf24j40_ed_levels);
switch (spi_get_device_id(devrec->spi)->driver_data) {
case MRF24J40:
case MRF24J40MA:
devrec->hw->phy->supported.tx_powers = mrf24j40ma_powers;
devrec->hw->phy->supported.tx_powers_size = ARRAY_SIZE(mrf24j40ma_powers);
devrec->hw->phy->flags |= WPAN_PHY_FLAG_TXPOWER;
break;
default:
break;
}
}
static int mrf24j40_probe(struct spi_device *spi)
{
int ret = -ENOMEM, irq_type;
struct ieee802154_hw *hw;
struct mrf24j40 *devrec;
dev_info(&spi->dev, "probe(). IRQ: %d\n", spi->irq);
/* Register with the 802154 subsystem */
hw = ieee802154_alloc_hw(sizeof(*devrec), &mrf24j40_ops);
if (!hw)
goto err_ret;
devrec = hw->priv;
devrec->spi = spi;
spi_set_drvdata(spi, devrec);
devrec->hw = hw;
devrec->hw->parent = &spi->dev;
devrec->hw->phy->supported.channels[0] = CHANNEL_MASK;
devrec->hw->flags = IEEE802154_HW_TX_OMIT_CKSUM | IEEE802154_HW_AFILT |
IEEE802154_HW_CSMA_PARAMS |
IEEE802154_HW_PROMISCUOUS;
devrec->hw->phy->flags = WPAN_PHY_FLAG_CCA_MODE |
WPAN_PHY_FLAG_CCA_ED_LEVEL;
mrf24j40_setup_tx_spi_messages(devrec);
mrf24j40_setup_rx_spi_messages(devrec);
mrf24j40_setup_irq_spi_messages(devrec);
devrec->regmap_short = devm_regmap_init_spi(spi,
&mrf24j40_short_regmap);
if (IS_ERR(devrec->regmap_short)) {
ret = PTR_ERR(devrec->regmap_short);
dev_err(&spi->dev, "Failed to allocate short register map: %d\n",
ret);
goto err_register_device;
}
devrec->regmap_long = devm_regmap_init(&spi->dev,
&mrf24j40_long_regmap_bus,
spi, &mrf24j40_long_regmap);
if (IS_ERR(devrec->regmap_long)) {
ret = PTR_ERR(devrec->regmap_long);
dev_err(&spi->dev, "Failed to allocate long register map: %d\n",
ret);
goto err_register_device;
}
if (spi->max_speed_hz > MAX_SPI_SPEED_HZ) {
dev_warn(&spi->dev, "spi clock above possible maximum: %d",
MAX_SPI_SPEED_HZ);
ret = -EINVAL;
goto err_register_device;
}
ret = mrf24j40_hw_init(devrec);
if (ret)
goto err_register_device;
mrf24j40_phy_setup(devrec);
/* request IRQF_TRIGGER_LOW as fallback default */
irq_type = irq_get_trigger_type(spi->irq);
if (!irq_type)
irq_type = IRQF_TRIGGER_LOW;
ret = devm_request_irq(&spi->dev, spi->irq, mrf24j40_isr,
irq_type, dev_name(&spi->dev), devrec);
if (ret) {
dev_err(printdev(devrec), "Unable to get IRQ");
goto err_register_device;
}
dev_dbg(printdev(devrec), "registered mrf24j40\n");
ret = ieee802154_register_hw(devrec->hw);
if (ret)
goto err_register_device;
return 0;
err_register_device:
ieee802154_free_hw(devrec->hw);
err_ret:
return ret;
}
static void mrf24j40_remove(struct spi_device *spi)
{
struct mrf24j40 *devrec = spi_get_drvdata(spi);
dev_dbg(printdev(devrec), "remove\n");
ieee802154_unregister_hw(devrec->hw);
ieee802154_free_hw(devrec->hw);
/* TODO: Will ieee802154_free_device() wait until ->xmit() is
* complete? */
}
static const struct of_device_id mrf24j40_of_match[] = {
{ .compatible = "microchip,mrf24j40", .data = (void *)MRF24J40 },
{ .compatible = "microchip,mrf24j40ma", .data = (void *)MRF24J40MA },
{ .compatible = "microchip,mrf24j40mc", .data = (void *)MRF24J40MC },
{ },
};
MODULE_DEVICE_TABLE(of, mrf24j40_of_match);
static const struct spi_device_id mrf24j40_ids[] = {
{ "mrf24j40", MRF24J40 },
{ "mrf24j40ma", MRF24J40MA },
{ "mrf24j40mc", MRF24J40MC },
{ },
};
MODULE_DEVICE_TABLE(spi, mrf24j40_ids);
static struct spi_driver mrf24j40_driver = {
.driver = {
.of_match_table = mrf24j40_of_match,
.name = "mrf24j40",
},
.id_table = mrf24j40_ids,
.probe = mrf24j40_probe,
.remove = mrf24j40_remove,
};
module_spi_driver(mrf24j40_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Alan Ott");
MODULE_DESCRIPTION("MRF24J40 SPI 802.15.4 Controller Driver");
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