This patch series adds the support for cc2520 radio and
provides device tree bindings for cc2520
Varka Bhadram (3):
ieee802154: cc2520: driver for TI cc2520 radio
ieee802154: cc2520: add driver to kernel build system
devicetree: add devicetree bindings for cc2520 driver
.../devicetree/bindings/net/ieee802154/cc2520.txt | 26 +
drivers/net/ieee802154/Kconfig | 11 +
drivers/net/ieee802154/Makefile | 1 +
drivers/net/ieee802154/cc2520.c | 805 ++++++++++++++++++++
include/linux/spi/cc2520.h | 176 +++++
5 files changed, 1019 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/ieee802154/cc2520.txt
create mode 100644 drivers/net/ieee802154/cc2520.c
create mode 100644 include/linux/spi/cc2520.h
--
1.7.9.5
Signed-off-by: Varka Bhadram <[email protected]>
---
drivers/net/ieee802154/cc2520.c | 805 +++++++++++++++++++++++++++++++++++++++
include/linux/spi/cc2520.h | 176 +++++++++
2 files changed, 981 insertions(+)
create mode 100644 drivers/net/ieee802154/cc2520.c
create mode 100644 include/linux/spi/cc2520.h
diff --git a/drivers/net/ieee802154/cc2520.c b/drivers/net/ieee802154/cc2520.c
new file mode 100644
index 0000000..e8b5993
--- /dev/null
+++ b/drivers/net/ieee802154/cc2520.c
@@ -0,0 +1,805 @@
+/* Driver for TI CC2520 802.15.4 Wireless-PAN Networking controller
+ *
+ * Copyright (C) 2014 Varka Bhadram <[email protected]>
+ * Md.Jamal Mohiuddin <[email protected]>
+ * P Sowjanya <[email protected]>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/cc2520.h>
+#include <linux/workqueue.h>
+#include <linux/interrupt.h>
+
+#include <linux/skbuff.h>
+
+#include <linux/pinctrl/consumer.h>
+
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/of_gpio.h>
+
+#include <net/mac802154.h>
+#include <net/wpan-phy.h>
+
+#define SPI_COMMAND_BUFFER 3
+#define HIGH 1
+#define LOW 0
+#define STATE_IDLE 0
+
+/*Driver private information */
+struct cc2520_private {
+ struct spi_device *spi;
+
+ struct ieee802154_dev *dev;
+
+ u8 *buf;
+ struct mutex buffer_mutex;
+
+ unsigned is_tx:1;
+ int fifo_irq;
+
+ int fifo_pin;
+ int fifop_pin;
+
+ struct work_struct fifop_irqwork;
+
+ spinlock_t lock;
+
+ struct completion tx_complete;
+};
+
+/*Generic Functions*/
+static int cc2520_cmd_strobe(struct cc2520_private *priv,
+ u8 cmd)
+{
+ int ret;
+ u8 status = 0xff;
+ struct spi_message msg;
+ struct spi_transfer xfer = {
+ .len = 0,
+ .tx_buf = priv->buf,
+ .rx_buf = priv->buf,
+ };
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfer, &msg);
+
+ mutex_lock(&priv->buffer_mutex);
+ priv->buf[xfer.len++] = cmd;
+ dev_vdbg(&priv->spi->dev,
+ "command strobe buf[0] = %02x\n",
+ priv->buf[0]);
+
+ ret = spi_sync(priv->spi, &msg);
+ if (!ret)
+ status = priv->buf[0];
+ dev_vdbg(&priv->spi->dev,
+ "buf[0] = %02x\n", priv->buf[0]);
+ mutex_unlock(&priv->buffer_mutex);
+
+ return ret;
+}
+
+static int cc2520_get_status(struct cc2520_private *priv,
+ u8 *status)
+{
+ int ret;
+ struct spi_message msg;
+ struct spi_transfer xfer = {
+ .len = 0,
+ .tx_buf = priv->buf,
+ .rx_buf = priv->buf,
+ };
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfer, &msg);
+
+ mutex_lock(&priv->buffer_mutex);
+ priv->buf[xfer.len++] = CC2520_CMD_SNOP;
+ dev_vdbg(&priv->spi->dev,
+ "get status command buf[0] = %02x\n", priv->buf[0]);
+
+ ret = spi_sync(priv->spi, &msg);
+ if (!ret)
+ *status = priv->buf[0];
+ dev_vdbg(&priv->spi->dev,
+ "buf[0] = %02x\n", priv->buf[0]);
+ mutex_unlock(&priv->buffer_mutex);
+
+ return ret;
+}
+
+static int cc2520_write_register(struct cc2520_private *priv,
+ u8 reg, u8 value)
+{
+ int status;
+ struct spi_message msg;
+ struct spi_transfer xfer = {
+ .len = 0,
+ .tx_buf = priv->buf,
+ .rx_buf = priv->buf,
+ };
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfer, &msg);
+
+ mutex_lock(&priv->buffer_mutex);
+
+ if (reg <= CC2520_FREG_MASK) {
+ priv->buf[xfer.len++] = CC2520_CMD_REGISTER_WRITE | reg;
+ priv->buf[xfer.len++] = value;
+ } else {
+ priv->buf[xfer.len++] = CC2520_CMD_MEMORY_WRITE;
+ priv->buf[xfer.len++] = reg;
+ priv->buf[xfer.len++] = value;
+ }
+ status = spi_sync(priv->spi, &msg);
+ if (msg.status)
+ status = msg.status;
+
+ mutex_unlock(&priv->buffer_mutex);
+
+ return status;
+}
+
+static int cc2520_read_register(struct cc2520_private *priv,
+ u8 reg, u8 *data)
+{
+
+ int status;
+ struct spi_message msg;
+ struct spi_transfer xfer1 = {
+ .len = 0,
+ .tx_buf = priv->buf,
+ .rx_buf = priv->buf,
+ };
+
+ struct spi_transfer xfer2 = {
+ .len = 1,
+ .rx_buf = data,
+ };
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfer1, &msg);
+ spi_message_add_tail(&xfer2, &msg);
+
+ mutex_lock(&priv->buffer_mutex);
+ priv->buf[xfer1.len++] = CC2520_CMD_MEMORY_READ;
+ priv->buf[xfer1.len++] = reg;
+
+ status = spi_sync(priv->spi, &msg);
+ dev_dbg(&priv->spi->dev,
+ "spi status = %d\n", status);
+ if (msg.status)
+ status = msg.status;
+
+ mutex_unlock(&priv->buffer_mutex);
+
+ return status;
+}
+
+static int cc2520_write_txfifo(struct cc2520_private *priv,
+ u8 *data, u8 len)
+{
+ int status;
+
+ /*
+ *length byte must include FCS even
+ *if it is calculated in the hardware
+ */
+ int len_byte = len + 2;
+
+ struct spi_message msg;
+
+ struct spi_transfer xfer_head = {
+ .len = 0,
+ .tx_buf = priv->buf,
+ .rx_buf = priv->buf,
+ };
+ struct spi_transfer xfer_len = {
+ .len = 1,
+ .tx_buf = &len_byte,
+ };
+ struct spi_transfer xfer_buf = {
+ .len = len,
+ .tx_buf = data,
+ };
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfer_head, &msg);
+ spi_message_add_tail(&xfer_len, &msg);
+ spi_message_add_tail(&xfer_buf, &msg);
+
+ mutex_lock(&priv->buffer_mutex);
+ priv->buf[xfer_head.len++] = CC2520_CMD_TXBUF;
+ dev_vdbg(&priv->spi->dev,
+ "TX_FIFO cmd buf[0] = %02x\n", priv->buf[0]);
+
+ status = spi_sync(priv->spi, &msg);
+ dev_vdbg(&priv->spi->dev, "status = %d\n", status);
+ if (msg.status)
+ status = msg.status;
+ dev_vdbg(&priv->spi->dev, "status = %d\n", status);
+ dev_vdbg(&priv->spi->dev, "buf[0] = %02x\n", priv->buf[0]);
+ mutex_unlock(&priv->buffer_mutex);
+
+ return status;
+}
+
+static int cc2520_read_rxfifo(struct cc2520_private *priv,
+ u8 *data, u8 *len, u8 *lqi)
+{
+ int status;
+ struct spi_message msg;
+
+ struct spi_transfer xfer_head = {
+ .len = 0,
+ .tx_buf = priv->buf,
+ .rx_buf = priv->buf,
+ };
+ struct spi_transfer xfer_buf = {
+ .len = *len,
+ .rx_buf = data,
+ };
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfer_head, &msg);
+ spi_message_add_tail(&xfer_buf, &msg);
+
+ mutex_lock(&priv->buffer_mutex);
+ priv->buf[xfer_head.len++] = CC2520_CMD_RXBUF;
+
+ dev_vdbg(&priv->spi->dev, "read rxfifo buf[0] = %02x\n", priv->buf[0]);
+ dev_vdbg(&priv->spi->dev, "buf[1] = %02x\n", priv->buf[1]);
+
+ status = spi_sync(priv->spi, &msg);
+ dev_vdbg(&priv->spi->dev, "status = %d\n", status);
+ if (msg.status)
+ status = msg.status;
+ dev_vdbg(&priv->spi->dev, "status = %d\n", status);
+ dev_vdbg(&priv->spi->dev,
+ "return status buf[0] = %02x\n", priv->buf[0]);
+ dev_vdbg(&priv->spi->dev, "length buf[1] = %02x\n", priv->buf[1]);
+
+ *lqi = data[priv->buf[1] - 1] & 0x7f;
+
+ mutex_unlock(&priv->buffer_mutex);
+
+ return status;
+}
+
+static int cc2520_start(struct ieee802154_dev *dev)
+{
+ return cc2520_cmd_strobe(dev->priv, CC2520_CMD_SRXON);
+}
+
+static void cc2520_stop(struct ieee802154_dev *dev)
+{
+ cc2520_cmd_strobe(dev->priv, CC2520_CMD_SRFOFF);
+}
+
+static int cc2520_tx(struct ieee802154_dev *dev, struct sk_buff *skb)
+{
+ struct cc2520_private *priv = dev->priv;
+ unsigned long flags;
+ int rc;
+ u8 status = 0;
+
+ rc = cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
+ if (rc)
+ goto err_tx;
+
+ rc = cc2520_write_txfifo(priv, skb->data, skb->len);
+ if (rc)
+ goto err_tx;
+
+ rc = cc2520_get_status(priv, &status);
+ if (rc)
+ goto err_tx;
+
+ if (status & CC2520_STATUS_TX_UNDERFLOW) {
+ dev_err(&priv->spi->dev, "cc2520 tx underflow exception\n");
+ goto err_tx;
+ }
+
+ spin_lock_irqsave(&priv->lock, flags);
+ BUG_ON(priv->is_tx);
+ priv->is_tx = 1;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ rc = cc2520_cmd_strobe(priv, CC2520_CMD_STXONCCA);
+ if (rc)
+ goto err;
+
+ rc = wait_for_completion_interruptible(&priv->tx_complete);
+ if (rc < 0)
+ goto err;
+
+ cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
+ cc2520_cmd_strobe(priv, CC2520_CMD_SRXON);
+
+ return rc;
+err:
+ spin_lock_irqsave(&priv->lock, flags);
+ priv->is_tx = 0;
+ spin_unlock_irqrestore(&priv->lock, flags);
+err_tx:
+ return rc;
+}
+
+
+static int cc2520_rx(struct cc2520_private *priv)
+{
+ u8 len = 0, lqi = 0, bytes = 1;
+ struct sk_buff *skb;
+
+ cc2520_read_rxfifo(priv, &len, &bytes, &lqi);
+
+ skb = alloc_skb(len, GFP_KERNEL);
+ if (!skb)
+ return -ENOMEM;
+
+ cc2520_read_rxfifo(priv, skb_put(skb, len), &len, &lqi);
+ if (len < 2) {
+ kfree_skb(skb);
+ return -EINVAL;
+ }
+
+ skb_trim(skb, skb->len - 2);
+
+ ieee802154_rx_irqsafe(priv->dev, skb, lqi);
+
+ dev_vdbg(&priv->spi->dev, "RXFIFO: %x %x\n", len, lqi);
+
+ return 0;
+}
+
+static int cc2520_ed(struct ieee802154_dev *dev, u8 *level)
+{
+ struct cc2520_private *priv = dev->priv;
+ u8 status = 0xff;
+ u8 rssi;
+ int ret;
+
+ ret = cc2520_read_register(priv , CC2520_RSSISTAT, &status);
+ if (ret)
+ return ret;
+
+ if (status != RSSI_VALID) {
+ ret = -EINVAL;
+ return ret;
+ }
+
+ ret = cc2520_read_register(priv , CC2520_RSSI, &rssi);
+ if (ret)
+ return ret;
+
+ /* level = RSSI(rssi) - OFFSET [dBm] : offset is 76dBm*/
+ *level = rssi - RSSI_OFFSET;
+
+ return ret;
+}
+
+static int cc2520_set_channel(struct ieee802154_dev *dev,
+ int page, int channel)
+{
+ struct cc2520_private *priv = dev->priv;
+ int ret;
+
+ might_sleep();
+ dev_dbg(&priv->spi->dev, "trying to set channel\n");
+
+ BUG_ON(page != 0);
+ BUG_ON(channel < CC2520_MINCHANNEL);
+ BUG_ON(channel > CC2520_MAXCHANNEL);
+
+ ret = cc2520_write_register(priv, CC2520_FREQCTRL,
+ 11 + 5*(channel - 11));
+
+ return ret;
+}
+
+static struct ieee802154_ops cc2520_ops = {
+ .owner = THIS_MODULE,
+ .start = cc2520_start,
+ .stop = cc2520_stop,
+ .xmit = cc2520_tx,
+ .ed = cc2520_ed,
+ .set_channel = cc2520_set_channel,
+};
+
+static int cc2520_register(struct cc2520_private *priv)
+{
+ int ret = -ENOMEM;
+
+ priv->dev = ieee802154_alloc_device(sizeof(*priv), &cc2520_ops);
+ if (!priv->dev)
+ goto err_ret;
+
+ priv->dev->priv = priv;
+ priv->dev->parent = &priv->spi->dev;
+ priv->dev->extra_tx_headroom = 0;
+
+ /* We do support only 2.4 Ghz */
+ priv->dev->phy->channels_supported[0] = 0x7FFF800;
+ priv->dev->flags = IEEE802154_HW_OMIT_CKSUM;
+
+ dev_vdbg(&priv->spi->dev, "registered cc2520\n");
+ ret = ieee802154_register_device(priv->dev);
+ if (ret)
+ goto err_free_device;
+
+ return 0;
+
+err_free_device:
+ ieee802154_free_device(priv->dev);
+err_ret:
+ return ret;
+}
+
+static void cc2520_unregister(struct cc2520_private *priv)
+{
+ ieee802154_unregister_device(priv->dev);
+ ieee802154_free_device(priv->dev);
+}
+
+static void cc2520_fifop_irqwork(struct work_struct *work)
+{
+ struct cc2520_private *priv
+ = container_of(work, struct cc2520_private, fifop_irqwork);
+
+ dev_dbg(&priv->spi->dev, "fifop interrupt received\n");
+
+ if (gpio_get_value(priv->fifo_pin))
+ cc2520_rx(priv);
+ else
+ dev_err(&priv->spi->dev, "rxfifo overflow\n");
+
+ cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
+ cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
+}
+
+static irqreturn_t cc2520_fifop_isr(int irq, void *data)
+{
+ struct cc2520_private *priv = data;
+
+ schedule_work(&priv->fifop_irqwork);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t cc2520_sfd_isr(int irq, void *data)
+{
+ struct cc2520_private *priv = data;
+
+ spin_lock(&priv->lock);
+ if (priv->is_tx) {
+ dev_dbg(&priv->spi->dev, "SFD for TX\n");
+ priv->is_tx = 0;
+ complete(&priv->tx_complete);
+ } else
+ dev_dbg(&priv->spi->dev, "SFD for RX\n");
+ spin_unlock(&priv->lock);
+
+ return IRQ_HANDLED;
+}
+
+static int cc2520_hw_init(struct cc2520_private *priv)
+{
+ u8 status = 0, state = 0xff;
+ int ret;
+ int timeout = 100;
+
+ ret = cc2520_read_register(priv, CC2520_FSMSTAT1, &state);
+ if (ret)
+ goto err_ret;
+
+ if (state != STATE_IDLE) {
+ ret = -EINVAL;
+ return ret;
+ }
+
+ do {
+ ret = cc2520_get_status(priv, &status);
+ if (ret)
+ goto err_ret;
+
+ if (timeout-- <= 0) {
+ dev_err(&priv->spi->dev, "oscillator start failed!\n");
+ return ret;
+ }
+ udelay(1);
+ } while (!(status & CC2520_STATUS_XOSC32M_STABLE));
+
+ dev_vdbg(&priv->spi->dev, "oscillator successfully brought up\n");
+
+ /*Registers default value: section 28.1 in Datasheet*/
+ ret = cc2520_write_register(priv, CC2520_TXPOWER, 0xF7);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_CCACTRL0, 0x1A);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_MDMCTRL0, 0x85);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_MDMCTRL1, 0x14);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_RXCTRL, 0x3f);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_FSCTRL, 0x5a);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_FSCAL1, 0x2b);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x11);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_ADCTEST0, 0x10);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_ADCTEST1, 0x0e);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_ADCTEST2, 0x03);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_FRMCTRL0, 0x60);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_FRMCTRL1, 0x03);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_FRMFILT0, 0x00);
+ if (ret)
+ goto err_ret;
+
+ ret = cc2520_write_register(priv, CC2520_FIFOPCTRL, 127);
+ if (ret)
+ goto err_ret;
+
+ return 0;
+
+err_ret:
+ return ret;
+}
+
+static struct cc2520_platform_data *
+cc2520_get_platform_data(struct spi_device *spi)
+{
+ struct cc2520_platform_data *pdata;
+ struct device_node __maybe_unused *np = spi->dev.of_node;
+ struct cc2520_private *priv = spi_get_drvdata(spi);
+
+ if (!IS_ENABLED(CONFIG_OF) || !np)
+ return spi->dev.platform_data;
+
+ pdata = devm_kzalloc(&spi->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ goto done;
+
+ pdata->fifo = of_get_named_gpio(np, "fifo-gpio", 0);
+ priv->fifo_pin = pdata->fifo;
+
+ pdata->fifop = of_get_named_gpio(np, "fifop-gpio", 0);
+ priv->fifop_pin = pdata->fifop;
+
+ pdata->sfd = of_get_named_gpio(np, "sfd-gpio", 0);
+ pdata->cca = of_get_named_gpio(np, "cca-gpio", 0);
+ pdata->vreg = of_get_named_gpio(np, "vreg-gpio", 0);
+ pdata->reset = of_get_named_gpio(np, "reset-gpio", 0);
+
+ spi->dev.platform_data = pdata;
+
+done:
+ return pdata;
+}
+
+/*Driver probe function*/
+static int cc2520_probe(struct spi_device *spi)
+{
+ struct cc2520_private *priv;
+ struct pinctrl *pinctrl;
+ struct cc2520_platform_data *pdata;
+ struct device_node __maybe_unused *np = spi->dev.of_node;
+ int ret;
+
+ priv = kzalloc(sizeof(struct cc2520_private), GFP_KERNEL);
+ if (!priv) {
+ ret = -ENOMEM;
+ goto err_free_local;
+ }
+
+ spi_set_drvdata(spi, priv);
+
+ pinctrl = devm_pinctrl_get_select_default(&spi->dev);
+ if (IS_ERR(pinctrl))
+ dev_warn(&spi->dev,
+ "pinctrl pins are not configured from the driver");
+
+ pdata = cc2520_get_platform_data(spi);
+ if (!pdata) {
+ dev_err(&spi->dev, "no platform data\n");
+ return -EINVAL;
+ }
+
+ mutex_init(&priv->buffer_mutex);
+ INIT_WORK(&priv->fifop_irqwork, cc2520_fifop_irqwork);
+ spin_lock_init(&priv->lock);
+ init_completion(&priv->tx_complete);
+
+ priv->spi = spi;
+
+ priv->buf = kzalloc(SPI_COMMAND_BUFFER, GFP_KERNEL);
+ if (!priv->buf) {
+ ret = -ENOMEM;
+ goto err_free_buf;
+ }
+
+ /*Request all the gpio's*/
+ if (gpio_is_valid(pdata->fifo)) {
+ ret = devm_gpio_request_one(&spi->dev, pdata->fifo,
+ GPIOF_IN, "fifo");
+ if (ret)
+ goto err_hw_init;
+ }
+
+ if (gpio_is_valid(pdata->cca)) {
+ ret = devm_gpio_request_one(&spi->dev, pdata->cca,
+ GPIOF_IN, "cca");
+ if (ret)
+ goto err_hw_init;
+ }
+
+ if (gpio_is_valid(pdata->fifop)) {
+ ret = devm_gpio_request_one(&spi->dev, pdata->fifop,
+ GPIOF_IN, "fifop");
+ if (ret)
+ goto err_hw_init;
+ }
+
+ if (gpio_is_valid(pdata->sfd)) {
+ ret = devm_gpio_request_one(&spi->dev, pdata->sfd,
+ GPIOF_IN, "sfd");
+ if (ret)
+ goto err_hw_init;
+ }
+
+ if (gpio_is_valid(pdata->reset)) {
+ ret = devm_gpio_request_one(&spi->dev, pdata->reset,
+ GPIOF_OUT_INIT_LOW, "reset");
+ if (ret)
+ goto err_hw_init;
+ }
+
+ if (gpio_is_valid(pdata->vreg)) {
+ ret = devm_gpio_request_one(&spi->dev, pdata->vreg,
+ GPIOF_OUT_INIT_LOW, "vreg");
+ if (ret)
+ goto err_hw_init;
+ }
+
+ gpio_set_value(pdata->vreg, HIGH);
+ udelay(100);
+
+ gpio_set_value(pdata->reset, HIGH);
+ udelay(200);
+
+ ret = cc2520_hw_init(priv);
+ if (ret)
+ goto err_hw_init;
+
+ /*Set up fifop interrupt */
+ priv->fifo_irq = gpio_to_irq(pdata->fifop);
+ ret = devm_request_irq(&spi->dev,
+ priv->fifo_irq,
+ cc2520_fifop_isr,
+ IRQF_TRIGGER_RISING,
+ dev_name(&spi->dev),
+ priv);
+ if (ret) {
+ dev_err(&spi->dev, "could not get fifop irq\n");
+ goto err_hw_init;
+ }
+
+ /*Set up sfd interrupt*/
+ ret = devm_request_irq(&spi->dev,
+ gpio_to_irq(pdata->sfd),
+ cc2520_sfd_isr,
+ IRQF_TRIGGER_FALLING,
+ dev_name(&spi->dev),
+ priv);
+ if (ret) {
+ dev_err(&spi->dev, "could not get sfd irq\n");
+ goto err_hw_init;
+ }
+
+ ret = cc2520_register(priv);
+ if (ret)
+ goto err_hw_init;
+
+ return 0;
+
+err_hw_init:
+ mutex_destroy(&priv->buffer_mutex);
+ flush_work(&priv->fifop_irqwork);
+
+err_free_buf:
+ kfree(priv->buf);
+
+err_free_local:
+ kfree(priv);
+
+ return ret;
+}
+
+/*Driver remove function*/
+static int cc2520_remove(struct spi_device *spi)
+{
+ struct cc2520_private *priv = spi_get_drvdata(spi);
+
+ cc2520_unregister(priv);
+
+ mutex_destroy(&priv->buffer_mutex);
+ flush_work(&priv->fifop_irqwork);
+
+ kfree(priv->buf);
+ kfree(priv);
+
+ return 0;
+}
+
+static const struct spi_device_id cc2520_ids[] = {
+ {"cc2520", 0},
+ {},
+};
+MODULE_DEVICE_TABLE(spi, cc2520_ids);
+
+static const struct of_device_id cc2520_of_ids[] = {
+ {.compatible = "ti,cc2520", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, cc2520_of_ids);
+
+/*SPI Driver Structure*/
+static struct spi_driver cc2520_driver = {
+ .driver = {
+ .name = "cc2520",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(cc2520_of_ids),
+ },
+ .id_table = cc2520_ids,
+ .probe = cc2520_probe,
+ .remove = cc2520_remove,
+};
+module_spi_driver(cc2520_driver);
+
+MODULE_DESCRIPTION("CC2520 Transceiver Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/spi/cc2520.h b/include/linux/spi/cc2520.h
new file mode 100644
index 0000000..68a2c88
--- /dev/null
+++ b/include/linux/spi/cc2520.h
@@ -0,0 +1,176 @@
+#ifndef __CC2520_H
+#define __CC2520_H
+
+#define RSSI_VALID 0
+#define RSSI_OFFSET 78
+#define CC2520_FREG_MASK 0x3F
+
+struct cc2520_platform_data {
+ int fifo;
+ int fifop;
+ int cca;
+ int sfd;
+ int reset;
+ int vreg;
+};
+
+enum cc2520_memory_size {
+ CC2520_RAM_SIZE = 640,
+ CC2520_FIFO_SIZE = 128,
+};
+
+enum cc2520_address {
+ CC2520RAM_TXFIFO = 0x100,
+ CC2520RAM_RXFIFO = 0x180,
+ CC2520RAM_IEEEADDR = 0x3EA,
+ CC2520RAM_PANID = 0x3F2,
+ CC2520RAM_SHORTADDR = 0x3F4,
+};
+
+/*status byte values */
+#define CC2520_STATUS_XOSC32M_STABLE (1 << 7)
+#define CC2520_STATUS_RSSI_VALID (1 << 6)
+#define CC2520_STATUS_TX_UNDERFLOW (1 << 3)
+
+/*IEEE 802.15.4 defined constants (2.4 GHz logical channels) */
+#define CC2520_MINCHANNEL 11
+#define CC2520_MAXCHANNEL 26
+#define CC2520_CHANNEL_SPACING 5
+
+/*command strobes*/
+#define CC2520_CMD_SNOP 0x00
+#define CC2520_CMD_IBUFLD 0x02
+#define CC2520_CMD_SIBUFEX 0x03
+#define CC2520_CMD_SSAMPLECCA 0x04
+#define CC2520_CMD_SRES 0x0f
+#define CC2520_CMD_MEMORY_MASK 0x0f
+#define CC2520_CMD_MEMORY_READ 0x10
+#define CC2520_CMD_MEMORY_WRITE 0x20
+#define CC2520_CMD_RXBUF 0x30
+#define CC2520_CMD_RXBUFCP 0x38
+#define CC2520_CMD_RXBUFMOV 0x32
+#define CC2520_CMD_TXBUF 0x3A
+#define CC2520_CMD_TXBUFCP 0x3E
+#define CC2520_CMD_RANDOM 0x3C
+#define CC2520_CMD_SXOSCON 0x40
+#define CC2520_CMD_STXCAL 0x41
+#define CC2520_CMD_SRXON 0x42
+#define CC2520_CMD_STXON 0x43
+#define CC2520_CMD_STXONCCA 0x44
+#define CC2520_CMD_SRFOFF 0x45
+#define CC2520_CMD_SXOSCOFF 0x46
+#define CC2520_CMD_SFLUSHRX 0x47
+#define CC2520_CMD_SFLUSHTX 0x48
+#define CC2520_CMD_SACK 0x49
+#define CC2520_CMD_SACKPEND 0x4A
+#define CC2520_CMD_SNACK 0x4B
+#define CC2520_CMD_SRXMASKBITSET 0x4C
+#define CC2520_CMD_SRXMASKBITCLR 0x4D
+#define CC2520_CMD_RXMASKAND 0x4E
+#define CC2520_CMD_RXMASKOR 0x4F
+#define CC2520_CMD_MEMCP 0x50
+#define CC2520_CMD_MEMCPR 0x52
+#define CC2520_CMD_MEMXCP 0x54
+#define CC2520_CMD_MEMXWR 0x56
+#define CC2520_CMD_BCLR 0x58
+#define CC2520_CMD_BSET 0x59
+#define CC2520_CMD_CTR_UCTR 0x60
+#define CC2520_CMD_CBCMAC 0x64
+#define CC2520_CMD_UCBCMAC 0x66
+#define CC2520_CMD_CCM 0x68
+#define CC2520_CMD_UCCM 0x6A
+#define CC2520_CMD_ECB 0x70
+#define CC2520_CMD_ECBO 0x72
+#define CC2520_CMD_ECBX 0x74
+#define CC2520_CMD_INC 0x78
+#define CC2520_CMD_ABORT 0x7F
+#define CC2520_CMD_REGISTER_READ 0x80
+#define CC2520_CMD_REGISTER_WRITE 0xC0
+
+/* status registers */
+#define CC2520_CHIPID 0x40
+#define CC2520_VERSION 0x42
+#define CC2520_EXTCLOCK 0x44
+#define CC2520_MDMCTRL0 0x46
+#define CC2520_MDMCTRL1 0x47
+#define CC2520_FREQEST 0x48
+#define CC2520_RXCTRL 0x4A
+#define CC2520_FSCTRL 0x4C
+#define CC2520_FSCAL0 0x4E
+#define CC2520_FSCAL1 0x4F
+#define CC2520_FSCAL2 0x50
+#define CC2520_FSCAL3 0x51
+#define CC2520_AGCCTRL0 0x52
+#define CC2520_AGCCTRL1 0x53
+#define CC2520_AGCCTRL2 0x54
+#define CC2520_AGCCTRL3 0x55
+#define CC2520_ADCTEST0 0x56
+#define CC2520_ADCTEST1 0x57
+#define CC2520_ADCTEST2 0x58
+#define CC2520_MDMTEST0 0x5A
+#define CC2520_MDMTEST1 0x5B
+#define CC2520_DACTEST0 0x5C
+#define CC2520_DACTEST1 0x5D
+#define CC2520_ATEST 0x5E
+#define CC2520_DACTEST2 0x5F
+#define CC2520_PTEST0 0x60
+#define CC2520_PTEST1 0x61
+#define CC2520_RESERVED 0x62
+#define CC2520_DPUBIST 0x7A
+#define CC2520_ACTBIST 0x7C
+#define CC2520_RAMBIST 0x7E
+
+/*frame registers*/
+#define CC2520_FRMFILT0 0x00
+#define CC2520_FRMFILT1 0x01
+#define CC2520_SRCMATCH 0x02
+#define CC2520_SRCSHORTEN0 0x04
+#define CC2520_SRCSHORTEN1 0x05
+#define CC2520_SRCSHORTEN2 0x06
+#define CC2520_SRCEXTEN0 0x08
+#define CC2520_SRCEXTEN1 0x09
+#define CC2520_SRCEXTEN2 0x0A
+#define CC2520_FRMCTRL0 0x0C
+#define CC2520_FRMCTRL1 0x0D
+#define CC2520_RXENABLE0 0x0E
+#define CC2520_RXENABLE1 0x0F
+#define CC2520_EXCFLAG0 0x10
+#define CC2520_EXCFLAG1 0x11
+#define CC2520_EXCFLAG2 0x12
+#define CC2520_EXCMASKA0 0x14
+#define CC2520_EXCMASKA1 0x15
+#define CC2520_EXCMASKA2 0x16
+#define CC2520_EXCMASKB0 0x18
+#define CC2520_EXCMASKB1 0x19
+#define CC2520_EXCMASKB2 0x1A
+#define CC2520_EXCBINDX0 0x1C
+#define CC2520_EXCBINDX1 0x1D
+#define CC2520_EXCBINDY0 0x1E
+#define CC2520_EXCBINDY1 0x1F
+#define CC2520_GPIOCTRL0 0x20
+#define CC2520_GPIOCTRL1 0x21
+#define CC2520_GPIOCTRL2 0x22
+#define CC2520_GPIOCTRL3 0x23
+#define CC2520_GPIOCTRL4 0x24
+#define CC2520_GPIOCTRL5 0x25
+#define CC2520_GPIOPOLARITY 0x26
+#define CC2520_GPIOCTRL 0x28
+#define CC2520_DPUCON 0x2A
+#define CC2520_DPUSTAT 0x2C
+#define CC2520_FREQCTRL 0x2E
+#define CC2520_FREQTUNE 0x2F
+#define CC2520_TXPOWER 0x30
+#define CC2520_TXCTRL 0x31
+#define CC2520_FSMSTAT0 0x32
+#define CC2520_FSMSTAT1 0x33
+#define CC2520_FIFOPCTRL 0x34
+#define CC2520_FSMCTRL 0x35
+#define CC2520_CCACTRL0 0x36
+#define CC2520_CCACTRL1 0x37
+#define CC2520_RSSI 0x38
+#define CC2520_RSSISTAT 0x39
+#define CC2520_RXFIRST 0x3C
+#define CC2520_RXFIFOCNT 0x3E
+#define CC2520_TXFIFOCNT 0x3F
+
+#endif
--
1.7.9.5
Signed-off-by: Varka Bhadram <[email protected]>
---
drivers/net/ieee802154/Kconfig | 11 +++++++++++
drivers/net/ieee802154/Makefile | 1 +
2 files changed, 12 insertions(+)
diff --git a/drivers/net/ieee802154/Kconfig b/drivers/net/ieee802154/Kconfig
index 3e89bea..680422f 100644
--- a/drivers/net/ieee802154/Kconfig
+++ b/drivers/net/ieee802154/Kconfig
@@ -51,3 +51,14 @@ config IEEE802154_MRF24J40
This driver can also be built as a module. To do so, say M here.
the module will be called 'mrf24j40'.
+
+config IEEE802154_CC2520
+ depends on IEEE802154_DRIVERS && MAC802154
+ tristate "cc2520 transceiver driver"
+ depends on SPI
+ ---help---
+ Say Y here to enable the CC2520 SPI 802.15.4 wireless
+ controller.
+
+ This driver can also be built as a module. To do so, say M here.
+ the module will be called 'cc2520'.
diff --git a/drivers/net/ieee802154/Makefile b/drivers/net/ieee802154/Makefile
index abb0c08..655cb95 100644
--- a/drivers/net/ieee802154/Makefile
+++ b/drivers/net/ieee802154/Makefile
@@ -2,3 +2,4 @@ obj-$(CONFIG_IEEE802154_FAKEHARD) += fakehard.o
obj-$(CONFIG_IEEE802154_FAKELB) += fakelb.o
obj-$(CONFIG_IEEE802154_AT86RF230) += at86rf230.o
obj-$(CONFIG_IEEE802154_MRF24J40) += mrf24j40.o
+obj-$(CONFIG_IEEE802154_CC2520) += cc2520.o
--
1.7.9.5
Signed-off-by: Varka Bhadram <[email protected]>
---
.../devicetree/bindings/net/ieee802154/cc2520.txt | 26 ++++++++++++++++++++
1 file changed, 26 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/ieee802154/cc2520.txt
diff --git a/Documentation/devicetree/bindings/net/ieee802154/cc2520.txt b/Documentation/devicetree/bindings/net/ieee802154/cc2520.txt
new file mode 100644
index 0000000..f0a749d
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/ieee802154/cc2520.txt
@@ -0,0 +1,26 @@
+CC2520 IEEE 802.15.4 Compatible Radio
+
+Required properties:
+ - compatible: should be "ti,cc2520"
+ - spi-max-frequency: maximal bus speed (8000000), should be set to 4000000 depends
+ sync or async operation mode
+ - reg: the chipselect index
+ - mode: SPI mode
+Example:
+
+ cc2520@0 {
+ compatible = "ti,cc2520";
+ reg = <0>;
+ spi-max-frequency = <4000000>;
+ mode = <1>;
+
+ pinctrl-names = "default";
+ pinctrl-0 = <&cc2520_cape_pins>; /*GPIO pin muxing details*/
+
+ fifo-gpio = <&gpio1 18 0>;
+ fifop-gpio = <&gpio1 19 0>;
+ sfd-gpio = <&gpio1 13 0>;
+ cca-gpio = <&gpio1 16 0>;
+ vreg-gpio = <&gpio0 31 0>;
+ reset-gpio = <&gpio1 12 0>;
+ };
--
1.7.9.5
Hi Varka,
On Mon, Jun 16, 2014 at 10:21:56AM +0530, Varka Bhadram wrote:
>
Maybe some more information about this chip in the commit msg?
> Signed-off-by: Varka Bhadram <[email protected]>
> ---
> drivers/net/ieee802154/cc2520.c | 805 +++++++++++++++++++++++++++++++++++++++
> include/linux/spi/cc2520.h | 176 +++++++++
> 2 files changed, 981 insertions(+)
> create mode 100644 drivers/net/ieee802154/cc2520.c
> create mode 100644 include/linux/spi/cc2520.h
>
> diff --git a/drivers/net/ieee802154/cc2520.c b/drivers/net/ieee802154/cc2520.c
> new file mode 100644
> index 0000000..e8b5993
> --- /dev/null
> +++ b/drivers/net/ieee802154/cc2520.c
> @@ -0,0 +1,805 @@
> +/* Driver for TI CC2520 802.15.4 Wireless-PAN Networking controller
> + *
> + * Copyright (C) 2014 Varka Bhadram <[email protected]>
> + * Md.Jamal Mohiuddin <[email protected]>
> + * P Sowjanya <[email protected]>
> + *
> + * 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.
> + *
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/gpio.h>
> +#include <linux/delay.h>
> +#include <linux/spi/spi.h>
> +#include <linux/spi/cc2520.h>
> +#include <linux/workqueue.h>
> +#include <linux/interrupt.h>
> +
> +#include <linux/skbuff.h>
> +
> +#include <linux/pinctrl/consumer.h>
> +
> +#include <linux/of_device.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_gpio.h>
> +
> +#include <net/mac802154.h>
> +#include <net/wpan-phy.h>
> +
> +#define SPI_COMMAND_BUFFER 3
> +#define HIGH 1
> +#define LOW 0
> +#define STATE_IDLE 0
> +
> +/*Driver private information */
> +struct cc2520_private {
> + struct spi_device *spi;
> +
> + struct ieee802154_dev *dev;
> +
> + u8 *buf;
> + struct mutex buffer_mutex;
> +
> + unsigned is_tx:1;
> + int fifo_irq;
> +
> + int fifo_pin;
> + int fifop_pin;
> +
> + struct work_struct fifop_irqwork;
> +
> + spinlock_t lock;
> +
> + struct completion tx_complete;
> +};
> +
> +/*Generic Functions*/
> +static int cc2520_cmd_strobe(struct cc2520_private *priv,
> + u8 cmd)
> +{
> + int ret;
> + u8 status = 0xff;
> + struct spi_message msg;
> + struct spi_transfer xfer = {
> + .len = 0,
> + .tx_buf = priv->buf,
> + .rx_buf = priv->buf,
> + };
> +
> + spi_message_init(&msg);
> + spi_message_add_tail(&xfer, &msg);
I see, you maybe looked at others drivers like at86rf230 and see what
they do there. I really don't like the lowlevel spi calls in the others
drivers. There are spi helper functions like 'spi_write_then_read' look
in drivers/spi/spi.c for the helper functions. Then you don't need the
buffer_mutex also.
> +
> + mutex_lock(&priv->buffer_mutex);
> + priv->buf[xfer.len++] = cmd;
> + dev_vdbg(&priv->spi->dev,
> + "command strobe buf[0] = %02x\n",
> + priv->buf[0]);
> +
> + ret = spi_sync(priv->spi, &msg);
> + if (!ret)
> + status = priv->buf[0];
> + dev_vdbg(&priv->spi->dev,
> + "buf[0] = %02x\n", priv->buf[0]);
> + mutex_unlock(&priv->buffer_mutex);
> +
> + return ret;
> +}
> +
....
> +
> +static void cc2520_unregister(struct cc2520_private *priv)
> +{
> + ieee802154_unregister_device(priv->dev);
> + ieee802154_free_device(priv->dev);
> +}
Only used in remove callback of module. It's small enough to do this in
the remove callback.
> +
> +static void cc2520_fifop_irqwork(struct work_struct *work)
> +{
> + struct cc2520_private *priv
> + = container_of(work, struct cc2520_private, fifop_irqwork);
> +
> + dev_dbg(&priv->spi->dev, "fifop interrupt received\n");
> +
> + if (gpio_get_value(priv->fifo_pin))
> + cc2520_rx(priv);
> + else
> + dev_err(&priv->spi->dev, "rxfifo overflow\n");
> +
> + cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
> + cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
> +}
> +
> +static irqreturn_t cc2520_fifop_isr(int irq, void *data)
> +{
> + struct cc2520_private *priv = data;
> +
> + schedule_work(&priv->fifop_irqwork);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t cc2520_sfd_isr(int irq, void *data)
> +{
> + struct cc2520_private *priv = data;
> +
> + spin_lock(&priv->lock);
You need to use here spin_lock_irqsave and spin_unlock_irqrestore here.
Please verify you locking with PROVE_LOCKING enabled in your kernel.
In your xmit callback you use a irqsave spinlocks there. You need always
save to the "strongest" context which is a interrupt in your case.
> + if (priv->is_tx) {
> + dev_dbg(&priv->spi->dev, "SFD for TX\n");
> + priv->is_tx = 0;
> + complete(&priv->tx_complete);
> + } else
> + dev_dbg(&priv->spi->dev, "SFD for RX\n");
make brackets in the else branch if you have brackets in the "if" branch.
You don't need to lock all the things here I think:
--snip
spin_lock_irqsave(&priv->lock, flags);
if (priv->is_tx) {
priv->is_tx = 0;
spin_unlock_irqrestore(&priv->lock, flags);
dev_dbg(&priv->spi->dev, "SFD for TX\n");
complete(&priv->tx_complete);
} else {
spin_unlock_irqrestore(&priv->lock, flags);
dev_dbg(&priv->spi->dev, "SFD for RX\n");
}
--snap
> + spin_unlock(&priv->lock);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int cc2520_hw_init(struct cc2520_private *priv)
> +{
> + u8 status = 0, state = 0xff;
> + int ret;
> + int timeout = 100;
> +
> + ret = cc2520_read_register(priv, CC2520_FSMSTAT1, &state);
> + if (ret)
> + goto err_ret;
> +
> + if (state != STATE_IDLE) {
> + ret = -EINVAL;
> + return ret;
return -EINVAL? saves the brackets ;)
> + }
> +
> + do {
> + ret = cc2520_get_status(priv, &status);
> + if (ret)
> + goto err_ret;
> +
> + if (timeout-- <= 0) {
> + dev_err(&priv->spi->dev, "oscillator start failed!\n");
> + return ret;
> + }
> + udelay(1);
> + } while (!(status & CC2520_STATUS_XOSC32M_STABLE));
> +
> + dev_vdbg(&priv->spi->dev, "oscillator successfully brought up\n");
> +
> + /*Registers default value: section 28.1 in Datasheet*/
> + ret = cc2520_write_register(priv, CC2520_TXPOWER, 0xF7);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_CCACTRL0, 0x1A);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_MDMCTRL0, 0x85);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_MDMCTRL1, 0x14);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_RXCTRL, 0x3f);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_FSCTRL, 0x5a);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_FSCAL1, 0x2b);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x11);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_ADCTEST0, 0x10);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_ADCTEST1, 0x0e);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_ADCTEST2, 0x03);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_FRMCTRL0, 0x60);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_FRMCTRL1, 0x03);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_FRMFILT0, 0x00);
> + if (ret)
> + goto err_ret;
> +
> + ret = cc2520_write_register(priv, CC2520_FIFOPCTRL, 127);
> + if (ret)
> + goto err_ret;
> +
> + return 0;
> +
> +err_ret:
> + return ret;
> +}
> +
> +static struct cc2520_platform_data *
> +cc2520_get_platform_data(struct spi_device *spi)
> +{
> + struct cc2520_platform_data *pdata;
> + struct device_node __maybe_unused *np = spi->dev.of_node;
> + struct cc2520_private *priv = spi_get_drvdata(spi);
> +
> + if (!IS_ENABLED(CONFIG_OF) || !np)
> + return spi->dev.platform_data;
> +
> + pdata = devm_kzalloc(&spi->dev, sizeof(*pdata), GFP_KERNEL);
> + if (!pdata)
> + goto done;
> +
> + pdata->fifo = of_get_named_gpio(np, "fifo-gpio", 0);
> + priv->fifo_pin = pdata->fifo;
> +
> + pdata->fifop = of_get_named_gpio(np, "fifop-gpio", 0);
> + priv->fifop_pin = pdata->fifop;
> +
> + pdata->sfd = of_get_named_gpio(np, "sfd-gpio", 0);
> + pdata->cca = of_get_named_gpio(np, "cca-gpio", 0);
> + pdata->vreg = of_get_named_gpio(np, "vreg-gpio", 0);
> + pdata->reset = of_get_named_gpio(np, "reset-gpio", 0);
> +
> + spi->dev.platform_data = pdata;
> +
> +done:
> + return pdata;
> +}
> +
> +/*Driver probe function*/
> +static int cc2520_probe(struct spi_device *spi)
> +{
> + struct cc2520_private *priv;
> + struct pinctrl *pinctrl;
> + struct cc2520_platform_data *pdata;
> + struct device_node __maybe_unused *np = spi->dev.of_node;
> + int ret;
> +
> + priv = kzalloc(sizeof(struct cc2520_private), GFP_KERNEL);
> + if (!priv) {
> + ret = -ENOMEM;
> + goto err_free_local;
> + }
why not devm_ calls?
> +
> + spi_set_drvdata(spi, priv);
> +
> + pinctrl = devm_pinctrl_get_select_default(&spi->dev);
> + if (IS_ERR(pinctrl))
> + dev_warn(&spi->dev,
> + "pinctrl pins are not configured from the driver");
> +
> + pdata = cc2520_get_platform_data(spi);
> + if (!pdata) {
> + dev_err(&spi->dev, "no platform data\n");
> + return -EINVAL;
memory leak of priv here.
> + }
> +
> + mutex_init(&priv->buffer_mutex);
> + INIT_WORK(&priv->fifop_irqwork, cc2520_fifop_irqwork);
I really don't like also the workqueue here. The at86rf230 use also a
workqueue but the mrf24j40 uses 'devm_request_threaded_irq'. A threaded
irq can also handle sync spi calls.
> + spin_lock_init(&priv->lock);
> + init_completion(&priv->tx_complete);
> +
> + priv->spi = spi;
> +
> + priv->buf = kzalloc(SPI_COMMAND_BUFFER, GFP_KERNEL);
> + if (!priv->buf) {
> + ret = -ENOMEM;
> + goto err_free_buf;
> + }
> +
> + /*Request all the gpio's*/
> + if (gpio_is_valid(pdata->fifo)) {
> + ret = devm_gpio_request_one(&spi->dev, pdata->fifo,
> + GPIOF_IN, "fifo");
> + if (ret)
> + goto err_hw_init;
> + }
> +
> + if (gpio_is_valid(pdata->cca)) {
> + ret = devm_gpio_request_one(&spi->dev, pdata->cca,
> + GPIOF_IN, "cca");
> + if (ret)
> + goto err_hw_init;
> + }
> +
> + if (gpio_is_valid(pdata->fifop)) {
> + ret = devm_gpio_request_one(&spi->dev, pdata->fifop,
> + GPIOF_IN, "fifop");
> + if (ret)
> + goto err_hw_init;
> + }
> +
> + if (gpio_is_valid(pdata->sfd)) {
> + ret = devm_gpio_request_one(&spi->dev, pdata->sfd,
> + GPIOF_IN, "sfd");
> + if (ret)
> + goto err_hw_init;
> + }
> +
> + if (gpio_is_valid(pdata->reset)) {
> + ret = devm_gpio_request_one(&spi->dev, pdata->reset,
> + GPIOF_OUT_INIT_LOW, "reset");
> + if (ret)
> + goto err_hw_init;
> + }
> +
> + if (gpio_is_valid(pdata->vreg)) {
> + ret = devm_gpio_request_one(&spi->dev, pdata->vreg,
> + GPIOF_OUT_INIT_LOW, "vreg");
> + if (ret)
> + goto err_hw_init;
> + }
You should check on the not optional pins if you can request them. You
use in the above code the pins vreg, reset, fifo_irq, sfd. And this
failed if the gpio's are not valid.
means:
if (!gpio_is_valid(pdata->vreg)) {
dev_err(....)
ret = -EINVAL;
goto ...;
}
on all pins which are needed to use your chip.
> +
> + gpio_set_value(pdata->vreg, HIGH);
> + udelay(100);
> +
> + gpio_set_value(pdata->reset, HIGH);
> + udelay(200);
> +
> + ret = cc2520_hw_init(priv);
> + if (ret)
> + goto err_hw_init;
> +
> + /*Set up fifop interrupt */
> + priv->fifo_irq = gpio_to_irq(pdata->fifop);
why is fifo_irq in your "private data"? This is only used in this function.
> + ret = devm_request_irq(&spi->dev,
> + priv->fifo_irq,
> + cc2520_fifop_isr,
> + IRQF_TRIGGER_RISING,
> + dev_name(&spi->dev),
> + priv);
> + if (ret) {
> + dev_err(&spi->dev, "could not get fifop irq\n");
> + goto err_hw_init;
> + }
> +
> + /*Set up sfd interrupt*/
> + ret = devm_request_irq(&spi->dev,
> + gpio_to_irq(pdata->sfd),
> + cc2520_sfd_isr,
> + IRQF_TRIGGER_FALLING,
> + dev_name(&spi->dev),
> + priv);
> + if (ret) {
> + dev_err(&spi->dev, "could not get sfd irq\n");
> + goto err_hw_init;
> + }
> +
> + ret = cc2520_register(priv);
> + if (ret)
> + goto err_hw_init;
> +
> + return 0;
> +
> +err_hw_init:
> + mutex_destroy(&priv->buffer_mutex);
> + flush_work(&priv->fifop_irqwork);
> +
> +err_free_buf:
> + kfree(priv->buf);
> +
> +err_free_local:
> + kfree(priv);
> +
> + return ret;
> +}
> +
> +/*Driver remove function*/
> +static int cc2520_remove(struct spi_device *spi)
> +{
> + struct cc2520_private *priv = spi_get_drvdata(spi);
> +
> + cc2520_unregister(priv);
> +
> + mutex_destroy(&priv->buffer_mutex);
> + flush_work(&priv->fifop_irqwork);
> +
> + kfree(priv->buf);
> + kfree(priv);
> +
> + return 0;
> +}
> +
> +static const struct spi_device_id cc2520_ids[] = {
> + {"cc2520", 0},
You don't need to set the driver_data to 0. Simple:
{ "cc2520", },
> + {},
> +};
> +MODULE_DEVICE_TABLE(spi, cc2520_ids);
> +
> +static const struct of_device_id cc2520_of_ids[] = {
> + {.compatible = "ti,cc2520", },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, cc2520_of_ids);
> +
> +/*SPI Driver Structure*/
> +static struct spi_driver cc2520_driver = {
> + .driver = {
> + .name = "cc2520",
> + .bus = &spi_bus_type,
> + .owner = THIS_MODULE,
> + .of_match_table = of_match_ptr(cc2520_of_ids),
> + },
> + .id_table = cc2520_ids,
> + .probe = cc2520_probe,
> + .remove = cc2520_remove,
> +};
> +module_spi_driver(cc2520_driver);
> +
> +MODULE_DESCRIPTION("CC2520 Transceiver Driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/spi/cc2520.h b/include/linux/spi/cc2520.h
> new file mode 100644
> index 0000000..68a2c88
> --- /dev/null
> +++ b/include/linux/spi/cc2520.h
In this location of header files are platform_data structs only. I think
you should leave the cc2520_platform_data in this file and move the rest
of declaration to you cc2520.c file.
> @@ -0,0 +1,176 @@
> +#ifndef __CC2520_H
> +#define __CC2520_H
> +
> +#define RSSI_VALID 0
> +#define RSSI_OFFSET 78
> +#define CC2520_FREG_MASK 0x3F
> +
> +struct cc2520_platform_data {
> + int fifo;
> + int fifop;
> + int cca;
> + int sfd;
> + int reset;
> + int vreg;
> +};
> +
- Alex
Hi Alex,
Thanks for the comments.
I will create a patch for the required changes with Reported-by
Alexander Aring <...> reply if this is okay for you.
On 06/16/2014 01:08 PM, Alexander Aring wrote:
> Hi Varka,
>
> On Mon, Jun 16, 2014 at 10:21:56AM +0530, Varka Bhadram wrote:
> Maybe some more information about this chip in the commit msg?
I will provide the proper commit messages in next version
>
> +/*Generic Functions*/
> +static int cc2520_cmd_strobe(struct cc2520_private *priv,
> + u8 cmd)
> +{
> + int ret;
> + u8 status = 0xff;
> + struct spi_message msg;
> + struct spi_transfer xfer = {
> + .len = 0,
> + .tx_buf = priv->buf,
> + .rx_buf = priv->buf,
> + };
> +
> + spi_message_init(&msg);
> + spi_message_add_tail(&xfer, &msg);
> I see, you maybe looked at others drivers like at86rf230 and see what
> they do there. I really don't like the lowlevel spi calls in the others
> drivers. There are spi helper functions like 'spi_write_then_read' look
> in drivers/spi/spi.c for the helper functions. Then you don't need the
> buffer_mutex also.
In at86rf230 driver first it hold the mutex lock for buffer then
__at86rf230_read_subreg()/ __at86rf230_write()
functions called. One more thing is that at the low level spi core is
holding the lock for the buffer data.
We can remove the buffer mutex.
>> +
>> + mutex_lock(&priv->buffer_mutex);
>> + priv->buf[xfer.len++] = cmd;
>> + dev_vdbg(&priv->spi->dev,
>> + "command strobe buf[0] = %02x\n",
>> + priv->buf[0]);
>> +
>> + ret = spi_sync(priv->spi, &msg);
>> + if (!ret)
>> + status = priv->buf[0];
>> + dev_vdbg(&priv->spi->dev,
>> + "buf[0] = %02x\n", priv->buf[0]);
>> + mutex_unlock(&priv->buffer_mutex);
>> +
>> + return ret;
>> +}
>> +
> ....
>
>> +
>> +static void cc2520_unregister(struct cc2520_private *priv)
>> +{
>> + ieee802154_unregister_device(priv->dev);
>> + ieee802154_free_device(priv->dev);
>> +}
> Only used in remove callback of module. It's small enough to do this in
> the remove callback.
>
Ya its nice . We can save the cpu context switching time also....
>> +
>> +static void cc2520_fifop_irqwork(struct work_struct *work)
>> +{
>> + struct cc2520_private *priv
>> + = container_of(work, struct cc2520_private, fifop_irqwork);
>> +
>> + dev_dbg(&priv->spi->dev, "fifop interrupt received\n");
>> +
>> + if (gpio_get_value(priv->fifo_pin))
>> + cc2520_rx(priv);
>> + else
>> + dev_err(&priv->spi->dev, "rxfifo overflow\n");
>> +
>> + cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
>> + cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
>> +}
>> +
>> +static irqreturn_t cc2520_fifop_isr(int irq, void *data)
>> +{
>> + struct cc2520_private *priv = data;
>> +
>> + schedule_work(&priv->fifop_irqwork);
>> +
>> + return IRQ_HANDLED;
>> +}
>> +
>> +static irqreturn_t cc2520_sfd_isr(int irq, void *data)
>> +{
>> + struct cc2520_private *priv = data;
>> +
>> + spin_lock(&priv->lock);
> You need to use here spin_lock_irqsave and spin_unlock_irqrestore here.
> Please verify you locking with PROVE_LOCKING enabled in your kernel.
>
> In your xmit callback you use a irqsave spinlocks there. You need always
> save to the "strongest" context which is a interrupt in your case.
This type of mechanism is needed when you want to remember the interrupt
status for the
IRQ/system.
>> + if (priv->is_tx) {
>> + dev_dbg(&priv->spi->dev, "SFD for TX\n");
>> + priv->is_tx = 0;
>> + complete(&priv->tx_complete);
>> + } else
>> + dev_dbg(&priv->spi->dev, "SFD for RX\n");
> make brackets in the else branch if you have brackets in the "if" branch.
>
> You don't need to lock all the things here I think:
>
> --snip
> spin_lock_irqsave(&priv->lock, flags);
> if (priv->is_tx) {
> priv->is_tx = 0;
> spin_unlock_irqrestore(&priv->lock, flags);
> dev_dbg(&priv->spi->dev, "SFD for TX\n");
> complete(&priv->tx_complete);
> } else {
> spin_unlock_irqrestore(&priv->lock, flags);
> dev_dbg(&priv->spi->dev, "SFD for RX\n");
> }
> --snap
>
Ya this can be the good approach...
>> + spin_unlock(&priv->lock);
>> +
>> + return IRQ_HANDLED
>> +/*Driver probe function*/
>> +static int cc2520_probe(struct spi_device *spi)
>> +{
>> + struct cc2520_private *priv;
>> + struct pinctrl *pinctrl;
>> + struct cc2520_platform_data *pdata;
>> + struct device_node __maybe_unused *np = spi->dev.of_node;
>> + int ret;
>> +
>> + priv = kzalloc(sizeof(struct cc2520_private), GFP_KERNEL);
>> + if (!priv) {
>> + ret = -ENOMEM;
>> + goto err_free_local;
>> + }
> why not devm_ calls?
I will surely change it to devm_....
>> +
>> + spi_set_drvdata(spi, priv);
>> +
>> + pinctrl = devm_pinctrl_get_select_default(&spi->dev);
>> +
>> + if (gpio_is_valid(pdata->vreg)) {
>> + ret = devm_gpio_request_one(&spi->dev, pdata->vreg,
>> + GPIOF_OUT_INIT_LOW, "vreg");
>> + if (ret)
>> + goto err_hw_init;
>> + }
> You should check on the not optional pins if you can request them. You
> use in the above code the pins vreg, reset, fifo_irq, sfd. And this
> failed if the gpio's are not valid.
>
> means:
>
> if (!gpio_is_valid(pdata->vreg)) {
> dev_err(....)
> ret = -EINVAL;
> goto ...;
> }
>
> on all pins which are needed to use your chip.
>
>> +
>> + gpio_set_value(pdata->vreg, HIGH);
>> + udelay(100);
>> +
>> + gpio_set_value(pdata->reset, HIGH);
>> + udelay(200);
>> +
>> + ret = cc2520_hw_init(priv);
>> + if (ret)
>> + goto err_hw_init;
>> +
>> + /*Set up fifop interrupt */
>> + priv->fifo_irq = gpio_to_irq(pdata->fifop);
> why is fifo_irq in your "private data"? This is only used in this function.
Ya this is my mistake. Previously i used in other place also.
>> + ret = devm_request_irq(&spi->dev,
>> + priv->fifo_irq,
>> + cc2520_fifop_isr,
>> + IRQF_TRIGGER_RISING,
>> + dev_name(&spi->dev),
>> + priv);
>> + if (ret) {
>> + dev_err(&spi->dev, "could not get fifop irq\n");
>> + goto err_hw_init;
>> + }
>> +
>> + /*Set up sfd interrupt*/
>> + ret = devm_request_irq(&spi->dev,
>> + gpio_to_irq(pdata->sfd),
>> + cc2520_sfd_isr,
>> + IRQF_TRIGGER_FALLING,
>> + dev_name(&spi->dev),
>> + priv);
>> + if (ret) {
>> + dev_err(&spi->dev, "could not get sfd irq\n");
>> + goto err_hw_init;
>> + }
>> +
>> + ret = cc2520_register(priv);
>> + if (ret)
>> + goto err_hw_init;
>> +
>> + return 0;
>> +
>> +err_hw_init:
>> + mutex_destroy(&priv->buffer_mutex);
>> + flush_work(&priv->fifop_irqwork);
>> +
>> +err_free_buf:
>> + kfree(priv->buf);
>> +
>> +err_free_local:
>> + kfree(priv);
>> +
>> + return ret;
>> +}
>> +
>> +/*Driver remove function*/
>> +static int cc2520_remove(struct spi_device *spi)
>> +{
>> + struct cc2520_private *priv = spi_get_drvdata(spi);
>> +
>> + cc2520_unregister(priv);
>> +
>> + mutex_destroy(&priv->buffer_mutex);
>> + flush_work(&priv->fifop_irqwork);
>> +
>> + kfree(priv->buf);
>> + kfree(priv);
>> +
>> + return 0;
>> +}
>> +
>> +static const struct spi_device_id cc2520_ids[] = {
>> + {"cc2520", 0},
> You don't need to set the driver_data to 0. Simple:
> { "cc2520", },
this does not make any difference.
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(spi, cc2520_ids);
>> +
>> +static const struct of_device_id cc2520_of_ids[] = {
>> + {.compatible = "ti,cc2520", },
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(of, cc2520_of_ids);
>> +
>> +/*SPI Driver Structure*/
>> +static struct spi_driver cc2520_driver = {
>> + .driver = {
>> + .name = "cc2520",
>> + .bus = &spi_bus_type,
>> + .owner = THIS_MODULE,
>> + .of_match_table = of_match_ptr(cc2520_of_ids),
>> + },
>> + .id_table = cc2520_ids,
>> + .probe = cc2520_probe,
>> + .remove = cc2520_remove,
>> +};
>> +module_spi_driver(cc2520_driver);
>> +
>> +MODULE_DESCRIPTION("CC2520 Transceiver Driver");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/include/linux/spi/cc2520.h b/include/linux/spi/cc2520.h
>> new file mode 100644
>> index 0000000..68a2c88
>> --- /dev/null
>> +++ b/include/linux/spi/cc2520.h
> In this location of header files are platform_data structs only. I think
> you should leave the cc2520_platform_data in this file and move the rest
> of declaration to you cc2520.c file.
>
I will move the code
>> @@ -0,0 +1,176 @@
>> +#ifndef __CC2520_H
>> +#define __CC2520_H
>> +
>> +#define RSSI_VALID 0
>> +#define RSSI_OFFSET 78
>> +#define CC2520_FREG_MASK 0x3F
>> +
>> +struct cc2520_platform_data {
>> + int fifo;
>> + int fifop;
>> + int cca;
>> + int sfd;
>> + int reset;
>> + int vreg;
>> +};
>> +
> - Alex
-Varka Bhadram
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Hi,
On Mon, Jun 16, 2014 at 02:21:19PM +0530, Varka Bhadram wrote:
...
> >>+
> >>+static void cc2520_unregister(struct cc2520_private *priv)
> >>+{
> >>+ ieee802154_unregister_device(priv->dev);
> >>+ ieee802154_free_device(priv->dev);
> >>+}
> >Only used in remove callback of module. It's small enough to do this in
> >the remove callback.
> >
There is no context switch here. It's a little bit faster because you
don't put some things on the stack. Alternative would be to add a inline
keyword to this function.
> Ya its nice . We can save the cpu context switching time also....
> >>+
> >>+static void cc2520_fifop_irqwork(struct work_struct *work)
> >>+{
> >>+ struct cc2520_private *priv
> >>+ = container_of(work, struct cc2520_private, fifop_irqwork);
> >>+
> >>+ dev_dbg(&priv->spi->dev, "fifop interrupt received\n");
> >>+
> >>+ if (gpio_get_value(priv->fifo_pin))
> >>+ cc2520_rx(priv);
> >>+ else
> >>+ dev_err(&priv->spi->dev, "rxfifo overflow\n");
> >>+
> >>+ cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
> >>+ cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
> >>+}
> >>+
> >>+static irqreturn_t cc2520_fifop_isr(int irq, void *data)
> >>+{
> >>+ struct cc2520_private *priv = data;
> >>+
> >>+ schedule_work(&priv->fifop_irqwork);
> >>+
> >>+ return IRQ_HANDLED;
> >>+}
> >>+
> >>+static irqreturn_t cc2520_sfd_isr(int irq, void *data)
> >>+{
> >>+ struct cc2520_private *priv = data;
> >>+
> >>+ spin_lock(&priv->lock);
> >You need to use here spin_lock_irqsave and spin_unlock_irqrestore here.
> >Please verify you locking with PROVE_LOCKING enabled in your kernel.
> >
> >In your xmit callback you use a irqsave spinlocks there. You need always
> >save to the "strongest" context which is a interrupt in your case.
> This type of mechanism is needed when you want to remember the interrupt
> status for the
> IRQ/system.
Yes you need I spinlock here, but spin_lock isn't irqsave but you need a
spin_lock function which is irqsave. This is
spin_lock_irqsave/spin_unlock_irqrestore.
You use these function in xmit callback for locking and that makes no
sense. You need to use spin_lock_irqsave/spin_unlock_irqrestore there of
course. But using in one function
spin_lock_irqsave/spin_unlock_irqrestore and in the other function
spin_lock/spin_unlock for the same spinlock is wrong.
In your case the strongest context is an irq, so you need for your
locking irqsave functions.
Please compile your kernel with PROVE_LOCKING and test your driver, then
you will see some warnings about deadlocks.
> >>+ if (priv->is_tx) {
> >>+ dev_dbg(&priv->spi->dev, "SFD for TX\n");
> >>+ priv->is_tx = 0;
> >>+ complete(&priv->tx_complete);
> >>+ } else
> >>+ dev_dbg(&priv->spi->dev, "SFD for RX\n");
> >make brackets in the else branch if you have brackets in the "if" branch.
> >
> >You don't need to lock all the things here I think:
> >
> >--snip
> > spin_lock_irqsave(&priv->lock, flags);
> > if (priv->is_tx) {
> > priv->is_tx = 0;
> > spin_unlock_irqrestore(&priv->lock, flags);
> > dev_dbg(&priv->spi->dev, "SFD for TX\n");
> > complete(&priv->tx_complete);
> > } else {
> > spin_unlock_irqrestore(&priv->lock, flags);
> > dev_dbg(&priv->spi->dev, "SFD for RX\n");
> > }
> >--snap
> >
> Ya this can be the good approach...
> >>+ spin_unlock(&priv->lock);
> >>+
> >>+ return IRQ_HANDLED
> >>+/*Driver probe function*/
> >>+static int cc2520_probe(struct spi_device *spi)
> >>+{
> >>+ struct cc2520_private *priv;
> >>+ struct pinctrl *pinctrl;
> >>+ struct cc2520_platform_data *pdata;
> >>+ struct device_node __maybe_unused *np = spi->dev.of_node;
> >>+ int ret;
> >>+
> >>+ priv = kzalloc(sizeof(struct cc2520_private), GFP_KERNEL);
> >>+ if (!priv) {
> >>+ ret = -ENOMEM;
> >>+ goto err_free_local;
> >>+ }
> >why not devm_ calls?
> I will surely change it to devm_....
> >>+
> >>+ spi_set_drvdata(spi, priv);
> >>+
> >>+ pinctrl = devm_pinctrl_get_select_default(&spi->dev);
> >>+
> >>+ if (gpio_is_valid(pdata->vreg)) {
> >>+ ret = devm_gpio_request_one(&spi->dev, pdata->vreg,
> >>+ GPIOF_OUT_INIT_LOW, "vreg");
> >>+ if (ret)
> >>+ goto err_hw_init;
> >>+ }
> >You should check on the not optional pins if you can request them. You
> >use in the above code the pins vreg, reset, fifo_irq, sfd. And this
s/above/below
> >failed if the gpio's are not valid.
> >
> >means:
> >
> >if (!gpio_is_valid(pdata->vreg)) {
> > dev_err(....)
> > ret = -EINVAL;
> > goto ...;
> >}
> >
> >on all pins which are needed to use your chip.
> >
> >>+
> >>+ gpio_set_value(pdata->vreg, HIGH);
> >>+ udelay(100);
> >>+
> >>+ gpio_set_value(pdata->reset, HIGH);
> >>+ udelay(200);
> >>+
> >>+ ret = cc2520_hw_init(priv);
> >>+ if (ret)
> >>+ goto err_hw_init;
> >>+
> >>+ /*Set up fifop interrupt */
> >>+ priv->fifo_irq = gpio_to_irq(pdata->fifop);
...
> >>+static const struct spi_device_id cc2520_ids[] = {
> >>+ {"cc2520", 0},
> >You don't need to set the driver_data to 0. Simple:
> > { "cc2520", },
> this does not make any difference.
Yes, but saves code. :-)
Usual prefer coding is:
"(no difference + more code) < (no difference + less code)"
- Alex