/* * Driver for Microchip MRF24J40 802.15.4 Wireless-PAN Networking controller * * Copyright (C) 2012 Alan Ott * Signal 11 Software * * 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; either version 2 of the License, or * (at your option) any later version. * * 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, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include #include #include #include #include #include #include /* MRF24J40 Short Address Registers */ #define REG_RXMCR 0x00 /* Receive MAC control */ #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_TXMCR 0x11 /* Transmit MAC control */ #define REG_PACON0 0x16 /* Power Amplifier Control */ #define REG_PACON1 0x17 /* Power Amplifier Control */ #define REG_PACON2 0x18 /* Power Amplifier Control */ #define REG_TXNCON 0x1B /* Transmit Normal FIFO Control */ #define REG_TXSTAT 0x24 /* TX MAC Status Register */ #define REG_SOFTRST 0x2A /* Soft Reset */ #define REG_TXSTBL 0x2E /* TX Stabilization */ #define REG_INTSTAT 0x31 /* Interrupt Status */ #define REG_INTCON 0x32 /* Interrupt Control */ #define REG_RFCTL 0x36 /* RF Control Mode Register */ #define REG_BBREG1 0x39 /* Baseband Registers */ #define REG_BBREG2 0x3A /* */ #define REG_BBREG6 0x3E /* */ #define REG_CCAEDTH 0x3F /* Energy Detection Threshold */ /* MRF24J40 Long Address Registers */ #define REG_RFCON0 0x200 /* RF Control Registers */ #define REG_RFCON1 0x201 #define REG_RFCON2 0x202 #define REG_RFCON3 0x203 #define REG_RFCON5 0x205 #define REG_RFCON6 0x206 #define REG_RFCON7 0x207 #define REG_RFCON8 0x208 #define REG_RSSI 0x210 #define REG_SLPCON0 0x211 /* Sleep Clock Control Registers */ #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_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 */ /* Device Private Data */ struct mrf24j40 { struct spi_device *spi; struct ieee802154_dev *dev; struct mutex buffer_mutex; /* only used to protect buf */ struct completion tx_complete; struct work_struct irqwork; u8 *buf; /* 3 bytes. Used for SPI single-register transfers. */ }; /* 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 int write_short_reg(struct mrf24j40 *devrec, u8 reg, u8 value) { int ret; struct spi_message msg; struct spi_transfer xfer = { .len = 2, .tx_buf = devrec->buf, .rx_buf = devrec->buf, }; spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); mutex_lock(&devrec->buffer_mutex); devrec->buf[0] = MRF24J40_WRITESHORT(reg); devrec->buf[1] = value; ret = spi_sync(devrec->spi, &msg); if (ret) dev_err(printdev(devrec), "SPI write Failed for short register 0x%hhx\n", reg); mutex_unlock(&devrec->buffer_mutex); return ret; } static int read_short_reg(struct mrf24j40 *devrec, u8 reg, u8 *val) { int ret = -1; struct spi_message msg; struct spi_transfer xfer = { .len = 2, .tx_buf = devrec->buf, .rx_buf = devrec->buf, }; spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); mutex_lock(&devrec->buffer_mutex); devrec->buf[0] = MRF24J40_READSHORT(reg); devrec->buf[1] = 0; ret = spi_sync(devrec->spi, &msg); if (ret) dev_err(printdev(devrec), "SPI read Failed for short register 0x%hhx\n", reg); else *val = devrec->buf[1]; mutex_unlock(&devrec->buffer_mutex); return ret; } static int read_long_reg(struct mrf24j40 *devrec, u16 reg, u8 *value) { int ret; u16 cmd; struct spi_message msg; struct spi_transfer xfer = { .len = 3, .tx_buf = devrec->buf, .rx_buf = devrec->buf, }; spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); cmd = MRF24J40_READLONG(reg); mutex_lock(&devrec->buffer_mutex); devrec->buf[0] = cmd >> 8 & 0xff; devrec->buf[1] = cmd & 0xff; devrec->buf[2] = 0; ret = spi_sync(devrec->spi, &msg); if (ret) dev_err(printdev(devrec), "SPI read Failed for long register 0x%hx\n", reg); else *value = devrec->buf[2]; mutex_unlock(&devrec->buffer_mutex); return ret; } static int write_long_reg(struct mrf24j40 *devrec, u16 reg, u8 val) { int ret; u16 cmd; struct spi_message msg; struct spi_transfer xfer = { .len = 3, .tx_buf = devrec->buf, .rx_buf = devrec->buf, }; spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); cmd = MRF24J40_WRITELONG(reg); mutex_lock(&devrec->buffer_mutex); devrec->buf[0] = cmd >> 8 & 0xff; devrec->buf[1] = cmd & 0xff; devrec->buf[2] = val; ret = spi_sync(devrec->spi, &msg); if (ret) dev_err(printdev(devrec), "SPI write Failed for long register 0x%hx\n", reg); mutex_unlock(&devrec->buffer_mutex); return ret; } /* 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) { int ret; u16 cmd; u8 lengths[2]; struct spi_message msg; struct spi_transfer addr_xfer = { .len = 2, .tx_buf = devrec->buf, }; struct spi_transfer lengths_xfer = { .len = 2, .tx_buf = &lengths, /* TODO: Is DMA really required for SPI? */ }; struct spi_transfer data_xfer = { .len = length, .tx_buf = data, }; /* 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; } spi_message_init(&msg); spi_message_add_tail(&addr_xfer, &msg); spi_message_add_tail(&lengths_xfer, &msg); spi_message_add_tail(&data_xfer, &msg); cmd = MRF24J40_WRITELONG(reg); mutex_lock(&devrec->buffer_mutex); devrec->buf[0] = cmd >> 8 & 0xff; devrec->buf[1] = cmd & 0xff; lengths[0] = 0x0; /* Header Length. Set to 0 for now. TODO */ lengths[1] = length; /* Total length */ ret = spi_sync(devrec->spi, &msg); if (ret) dev_err(printdev(devrec), "SPI write Failed for TX buf\n"); mutex_unlock(&devrec->buffer_mutex); return ret; } static int mrf24j40_read_rx_buf(struct mrf24j40 *devrec, u8 *data, u8 *len, u8 *lqi) { u8 rx_len; u8 addr[2]; u8 lqi_rssi[2]; u16 cmd; int ret; struct spi_message msg; struct spi_transfer addr_xfer = { .len = 2, .tx_buf = &addr, }; struct spi_transfer data_xfer = { .len = 0x0, /* set below */ .rx_buf = data, }; struct spi_transfer status_xfer = { .len = 2, .rx_buf = &lqi_rssi, }; /* Get the length of the data in the RX FIFO. The length in this * register exclues the 1-byte length field at the beginning. */ ret = read_long_reg(devrec, REG_RX_FIFO, &rx_len); if (ret) goto out; /* Range check the RX FIFO length, accounting for the one-byte * length field at the begining. */ if (rx_len > RX_FIFO_SIZE-1) { dev_err(printdev(devrec), "Invalid length read from device. Performing short read.\n"); rx_len = RX_FIFO_SIZE-1; } if (rx_len > *len) { /* Passed in buffer wasn't big enough. Should never happen. */ dev_err(printdev(devrec), "Buffer not big enough. Performing short read\n"); rx_len = *len; } /* Set up the commands to read the data. */ cmd = MRF24J40_READLONG(REG_RX_FIFO+1); addr[0] = cmd >> 8 & 0xff; addr[1] = cmd & 0xff; data_xfer.len = rx_len; spi_message_init(&msg); spi_message_add_tail(&addr_xfer, &msg); spi_message_add_tail(&data_xfer, &msg); spi_message_add_tail(&status_xfer, &msg); ret = spi_sync(devrec->spi, &msg); if (ret) { dev_err(printdev(devrec), "SPI RX Buffer Read Failed.\n"); goto out; } *lqi = lqi_rssi[0]; *len = rx_len; #ifdef DEBUG print_hex_dump(KERN_DEBUG, "mrf24j40 rx: ", DUMP_PREFIX_OFFSET, 16, 1, data, *len, 0); printk(KERN_DEBUG "mrf24j40 rx: lqi: %02hhx rssi: %02hhx\n", lqi_rssi[0], lqi_rssi[1]); #endif out: return ret; } static int mrf24j40_tx(struct ieee802154_dev *dev, struct sk_buff *skb) { struct mrf24j40 *devrec = dev->priv; u8 val; int ret = 0; dev_dbg(printdev(devrec), "tx packet of %d bytes\n", skb->len); ret = write_tx_buf(devrec, 0x000, skb->data, skb->len); if (ret) goto err; /* Set TXNTRIG bit of TXNCON to send packet */ ret = read_short_reg(devrec, REG_TXNCON, &val); if (ret) goto err; val |= 0x1; /* Set TXNACKREQ if the ACK bit is set in the packet. */ if (skb->data[0] & IEEE802154_FC_ACK_REQ) val |= 0x4; write_short_reg(devrec, REG_TXNCON, val); INIT_COMPLETION(devrec->tx_complete); /* Wait for the device to send the TX complete interrupt. */ ret = wait_for_completion_interruptible_timeout( &devrec->tx_complete, 5 * HZ); if (ret == -ERESTARTSYS) goto err; if (ret == 0) { dev_warn(printdev(devrec), "Timeout waiting for TX interrupt\n"); ret = -ETIMEDOUT; goto err; } /* Check for send error from the device. */ ret = read_short_reg(devrec, REG_TXSTAT, &val); if (ret) goto err; if (val & 0x1) { dev_dbg(printdev(devrec), "Error Sending. Retry count exceeded\n"); ret = -ECOMM; /* TODO: Better error code ? */ } else dev_dbg(printdev(devrec), "Packet Sent\n"); err: return ret; } static int mrf24j40_ed(struct ieee802154_dev *dev, u8 *level) { /* TODO: */ printk(KERN_WARNING "mrf24j40: ed not implemented\n"); *level = 0; return 0; } static int mrf24j40_start(struct ieee802154_dev *dev) { struct mrf24j40 *devrec = dev->priv; u8 val; int ret; dev_dbg(printdev(devrec), "start\n"); ret = read_short_reg(devrec, REG_INTCON, &val); if (ret) return ret; val &= ~(0x1|0x8); /* Clear TXNIE and RXIE. Enable interrupts */ write_short_reg(devrec, REG_INTCON, val); return 0; } static void mrf24j40_stop(struct ieee802154_dev *dev) { struct mrf24j40 *devrec = dev->priv; u8 val; int ret; dev_dbg(printdev(devrec), "stop\n"); ret = read_short_reg(devrec, REG_INTCON, &val); if (ret) return; val |= 0x1|0x8; /* Set TXNIE and RXIE. Disable Interrupts */ write_short_reg(devrec, REG_INTCON, val); return; } static int mrf24j40_set_channel(struct ieee802154_dev *dev, int page, int channel) { struct mrf24j40 *devrec = dev->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) << 4 | 0x03; write_long_reg(devrec, REG_RFCON0, val); /* RF Reset */ ret = read_short_reg(devrec, REG_RFCTL, &val); if (ret) return ret; val |= 0x04; write_short_reg(devrec, REG_RFCTL, val); val &= ~0x04; write_short_reg(devrec, REG_RFCTL, val); udelay(SET_CHANNEL_DELAY_US); /* per datasheet */ return 0; } static int mrf24j40_filter(struct ieee802154_dev *dev, struct ieee802154_hw_addr_filt *filt, unsigned long changed) { struct mrf24j40 *devrec = dev->priv; dev_dbg(printdev(devrec), "filter\n"); if (changed & IEEE802515_AFILT_SADDR_CHANGED) { /* Short Addr */ u8 addrh, addrl; addrh = filt->short_addr >> 8 & 0xff; addrl = filt->short_addr & 0xff; write_short_reg(devrec, REG_SADRH, addrh); write_short_reg(devrec, REG_SADRL, addrl); dev_dbg(printdev(devrec), "Set short addr to %04hx\n", filt->short_addr); } if (changed & IEEE802515_AFILT_IEEEADDR_CHANGED) { /* Device Address */ int i; for (i = 0; i < 8; i++) write_short_reg(devrec, REG_EADR0+i, filt->ieee_addr[7-i]); #ifdef DEBUG printk(KERN_DEBUG "Set long addr to: "); for (i = 0; i < 8; i++) printk("%02hhx ", filt->ieee_addr[i]); printk(KERN_DEBUG "\n"); #endif } if (changed & IEEE802515_AFILT_PANID_CHANGED) { /* PAN ID */ u8 panidl, panidh; panidh = filt->pan_id >> 8 & 0xff; panidl = filt->pan_id & 0xff; write_short_reg(devrec, REG_PANIDH, panidh); write_short_reg(devrec, REG_PANIDL, panidl); dev_dbg(printdev(devrec), "Set PANID to %04hx\n", filt->pan_id); } if (changed & IEEE802515_AFILT_PANC_CHANGED) { /* Pan Coordinator */ u8 val; int ret; ret = read_short_reg(devrec, REG_RXMCR, &val); if (ret) return ret; if (filt->pan_coord) val |= 0x8; else val &= ~0x8; write_short_reg(devrec, REG_RXMCR, val); /* 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 int mrf24j40_handle_rx(struct mrf24j40 *devrec) { u8 len = RX_FIFO_SIZE; u8 lqi = 0; u8 val; int ret = 0; struct sk_buff *skb; /* Turn off reception of packets off the air. This prevents the * device from overwriting the buffer while we're reading it. */ ret = read_short_reg(devrec, REG_BBREG1, &val); if (ret) goto out; val |= 4; /* SET RXDECINV */ write_short_reg(devrec, REG_BBREG1, val); skb = alloc_skb(len, GFP_KERNEL); if (!skb) { ret = -ENOMEM; goto out; } ret = mrf24j40_read_rx_buf(devrec, skb_put(skb, len), &len, &lqi); if (ret < 0) { dev_err(printdev(devrec), "Failure reading RX FIFO\n"); kfree_skb(skb); ret = -EINVAL; goto out; } /* Cut off the checksum */ skb_trim(skb, len-2); /* TODO: Other drivers call ieee20154_rx_irqsafe() here (eg: cc2040, * also from a workqueue). I think irqsafe is not necessary here. * Can someone confirm? */ ieee802154_rx_irqsafe(devrec->dev, skb, lqi); dev_dbg(printdev(devrec), "RX Handled\n"); out: /* Turn back on reception of packets off the air. */ ret = read_short_reg(devrec, REG_BBREG1, &val); if (ret) return ret; val &= ~0x4; /* Clear RXDECINV */ write_short_reg(devrec, REG_BBREG1, val); return ret; } static struct ieee802154_ops mrf24j40_ops = { .owner = THIS_MODULE, .xmit = mrf24j40_tx, .ed = mrf24j40_ed, .start = mrf24j40_start, .stop = mrf24j40_stop, .set_channel = mrf24j40_set_channel, .set_hw_addr_filt = mrf24j40_filter, }; static irqreturn_t mrf24j40_isr(int irq, void *data) { struct mrf24j40 *devrec = data; disable_irq_nosync(irq); schedule_work(&devrec->irqwork); return IRQ_HANDLED; } static void mrf24j40_isrwork(struct work_struct *work) { struct mrf24j40 *devrec = container_of(work, struct mrf24j40, irqwork); u8 intstat; int ret; /* Read the interrupt status */ ret = read_short_reg(devrec, REG_INTSTAT, &intstat); if (ret) goto out; /* Check for TX complete */ if (intstat & 0x1) complete(&devrec->tx_complete); /* Check for Rx */ if (intstat & 0x8) mrf24j40_handle_rx(devrec); out: enable_irq(devrec->spi->irq); } static int mrf24j40_probe(struct spi_device *spi) { int ret = -ENOMEM; u8 val; struct mrf24j40 *devrec; struct pinctrl *pinctrl; printk(KERN_INFO "mrf24j40: probe(). IRQ: %d\n", spi->irq); devrec = kzalloc(sizeof(struct mrf24j40), GFP_KERNEL); if (!devrec) goto err_devrec; devrec->buf = kzalloc(3, GFP_KERNEL); if (!devrec->buf) goto err_buf; pinctrl = devm_pinctrl_get_select_default(&spi->dev); if (IS_ERR(pinctrl)) dev_warn(&spi->dev, "pinctrl pins are not configured from the driver"); spi->mode = SPI_MODE_0; /* TODO: Is this appropriate for right here? */ if (spi->max_speed_hz > MAX_SPI_SPEED_HZ) spi->max_speed_hz = MAX_SPI_SPEED_HZ; mutex_init(&devrec->buffer_mutex); init_completion(&devrec->tx_complete); INIT_WORK(&devrec->irqwork, mrf24j40_isrwork); devrec->spi = spi; spi_set_drvdata(spi, devrec); /* Register with the 802154 subsystem */ devrec->dev = ieee802154_alloc_device(0, &mrf24j40_ops); if (!devrec->dev) goto err_alloc_dev; devrec->dev->priv = devrec; devrec->dev->parent = &devrec->spi->dev; devrec->dev->phy->channels_supported[0] = CHANNEL_MASK; devrec->dev->flags = IEEE802154_HW_OMIT_CKSUM|IEEE802154_HW_AACK; dev_dbg(printdev(devrec), "registered mrf24j40\n"); ret = ieee802154_register_device(devrec->dev); if (ret) goto err_register_device; /* Initialize the device. From datasheet section 3.2: Initialization. */ write_short_reg(devrec, REG_SOFTRST, 0x07); write_short_reg(devrec, REG_PACON2, 0x98); write_short_reg(devrec, REG_TXSTBL, 0x95); write_long_reg(devrec, REG_RFCON0, 0x03); write_long_reg(devrec, REG_RFCON1, 0x01); write_long_reg(devrec, REG_RFCON2, 0x80); write_long_reg(devrec, REG_RFCON6, 0x90); write_long_reg(devrec, REG_RFCON7, 0x80); write_long_reg(devrec, REG_RFCON8, 0x10); write_long_reg(devrec, REG_SLPCON1, 0x21); write_short_reg(devrec, REG_BBREG2, 0x80); write_short_reg(devrec, REG_CCAEDTH, 0x60); write_short_reg(devrec, REG_BBREG6, 0x40); write_short_reg(devrec, REG_RFCTL, 0x04); write_short_reg(devrec, REG_RFCTL, 0x0); udelay(192); /* Set RX Mode. RXMCR<1:0>: 0x0 normal, 0x1 promisc, 0x2 error */ ret = read_short_reg(devrec, REG_RXMCR, &val); if (ret) goto err_read_reg; val &= ~0x3; /* Clear RX mode (normal) */ write_short_reg(devrec, REG_RXMCR, val); ret = request_irq(spi->irq, mrf24j40_isr, IRQF_TRIGGER_FALLING, dev_name(&spi->dev), devrec); if (ret) { dev_err(printdev(devrec), "Unable to get IRQ"); goto err_irq; } return 0; err_irq: err_read_reg: ieee802154_unregister_device(devrec->dev); err_register_device: ieee802154_free_device(devrec->dev); err_alloc_dev: kfree(devrec->buf); err_buf: kfree(devrec); err_devrec: return ret; } static int mrf24j40_remove(struct spi_device *spi) { struct mrf24j40 *devrec = spi_get_drvdata(spi); dev_dbg(printdev(devrec), "remove\n"); free_irq(spi->irq, devrec); flush_work(&devrec->irqwork); /* TODO: Is this the right call? */ ieee802154_unregister_device(devrec->dev); ieee802154_free_device(devrec->dev); /* TODO: Will ieee802154_free_device() wait until ->xmit() is * complete? */ /* Clean up the SPI stuff. */ spi_set_drvdata(spi, NULL); kfree(devrec->buf); kfree(devrec); return 0; } static const struct spi_device_id mrf24j40_ids[] = { { "mrf24j40", 0 }, { "mrf24j40ma", 0 }, { }, }; MODULE_DEVICE_TABLE(spi, mrf24j40_ids); static struct spi_driver mrf24j40_driver = { .driver = { .name = "mrf24j40", .bus = &spi_bus_type, .owner = THIS_MODULE, }, .id_table = mrf24j40_ids, .probe = mrf24j40_probe, .remove = mrf24j40_remove, }; static int __init mrf24j40_init(void) { return spi_register_driver(&mrf24j40_driver); } static void __exit mrf24j40_exit(void) { spi_unregister_driver(&mrf24j40_driver); } module_init(mrf24j40_init); module_exit(mrf24j40_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Alan Ott"); MODULE_DESCRIPTION("MRF24J40 SPI 802.15.4 Controller Driver");