From dfc768fbe618d97d0dde88c8e8e586201b0a7587 Mon Sep 17 00:00:00 2001 From: Stefan Wahren Date: Mon, 29 May 2017 13:57:25 +0200 Subject: [PATCH] net: qualcomm: add QCA7000 UART driver This patch adds the Ethernet over UART driver for the Qualcomm QCA7000 HomePlug GreenPHY. Signed-off-by: Stefan Wahren Reviewed-by: Lino Sanfilippo Signed-off-by: David S. Miller --- drivers/net/ethernet/qualcomm/Kconfig | 16 + drivers/net/ethernet/qualcomm/Makefile | 2 + drivers/net/ethernet/qualcomm/qca_7k_common.h | 6 + drivers/net/ethernet/qualcomm/qca_uart.c | 423 ++++++++++++++++++ 4 files changed, 447 insertions(+) create mode 100644 drivers/net/ethernet/qualcomm/qca_uart.c diff --git a/drivers/net/ethernet/qualcomm/Kconfig b/drivers/net/ethernet/qualcomm/Kconfig index b4c369dccde7..877675a27b9f 100644 --- a/drivers/net/ethernet/qualcomm/Kconfig +++ b/drivers/net/ethernet/qualcomm/Kconfig @@ -30,6 +30,22 @@ config QCA7000_SPI To compile this driver as a module, choose M here. The module will be called qcaspi. +config QCA7000_UART + tristate "Qualcomm Atheros QCA7000 UART support" + select QCA7000 + depends on SERIAL_DEV_BUS && OF + ---help--- + This UART protocol driver supports the Qualcomm Atheros QCA7000. + + Currently the driver assumes these device UART settings: + Data bits: 8 + Parity: None + Stop bits: 1 + Flow control: None + + To compile this driver as a module, choose M here. The module + will be called qcauart. + config QCOM_EMAC tristate "Qualcomm Technologies, Inc. EMAC Gigabit Ethernet support" depends on HAS_DMA && HAS_IOMEM diff --git a/drivers/net/ethernet/qualcomm/Makefile b/drivers/net/ethernet/qualcomm/Makefile index 65556ca185a6..92fa7c4da90a 100644 --- a/drivers/net/ethernet/qualcomm/Makefile +++ b/drivers/net/ethernet/qualcomm/Makefile @@ -5,5 +5,7 @@ obj-$(CONFIG_QCA7000) += qca_7k_common.o obj-$(CONFIG_QCA7000_SPI) += qcaspi.o qcaspi-objs := qca_7k.o qca_debug.o qca_spi.o +obj-$(CONFIG_QCA7000_UART) += qcauart.o +qcauart-objs := qca_uart.o obj-y += emac/ diff --git a/drivers/net/ethernet/qualcomm/qca_7k_common.h b/drivers/net/ethernet/qualcomm/qca_7k_common.h index 07bdd6c4f728..928554f11e35 100644 --- a/drivers/net/ethernet/qualcomm/qca_7k_common.h +++ b/drivers/net/ethernet/qualcomm/qca_7k_common.h @@ -122,6 +122,12 @@ static inline void qcafrm_fsm_init_spi(struct qcafrm_handle *handle) handle->state = handle->init; } +static inline void qcafrm_fsm_init_uart(struct qcafrm_handle *handle) +{ + handle->init = QCAFRM_WAIT_AA1; + handle->state = handle->init; +} + /* Gather received bytes and try to extract a full Ethernet frame * by following a simple state machine. * diff --git a/drivers/net/ethernet/qualcomm/qca_uart.c b/drivers/net/ethernet/qualcomm/qca_uart.c new file mode 100644 index 000000000000..db6068cd7a1f --- /dev/null +++ b/drivers/net/ethernet/qualcomm/qca_uart.c @@ -0,0 +1,423 @@ +/* + * Copyright (c) 2011, 2012, Qualcomm Atheros Communications Inc. + * Copyright (c) 2017, I2SE GmbH + * + * Permission to use, copy, modify, and/or distribute this software + * for any purpose with or without fee is hereby granted, provided + * that the above copyright notice and this permission notice appear + * in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL + * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL + * THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM + * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, + * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN + * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* This module implements the Qualcomm Atheros UART protocol for + * kernel-based UART device; it is essentially an Ethernet-to-UART + * serial converter; + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "qca_7k_common.h" + +#define QCAUART_DRV_VERSION "0.1.0" +#define QCAUART_DRV_NAME "qcauart" +#define QCAUART_TX_TIMEOUT (1 * HZ) + +struct qcauart { + struct net_device *net_dev; + spinlock_t lock; /* transmit lock */ + struct work_struct tx_work; /* Flushes transmit buffer */ + + struct serdev_device *serdev; + struct qcafrm_handle frm_handle; + struct sk_buff *rx_skb; + + unsigned char *tx_head; /* pointer to next XMIT byte */ + int tx_left; /* bytes left in XMIT queue */ + unsigned char *tx_buffer; +}; + +static int +qca_tty_receive(struct serdev_device *serdev, const unsigned char *data, + size_t count) +{ + struct qcauart *qca = serdev_device_get_drvdata(serdev); + struct net_device *netdev = qca->net_dev; + struct net_device_stats *n_stats = &netdev->stats; + size_t i; + + if (!qca->rx_skb) { + qca->rx_skb = netdev_alloc_skb_ip_align(netdev, + netdev->mtu + + VLAN_ETH_HLEN); + if (!qca->rx_skb) { + n_stats->rx_errors++; + n_stats->rx_dropped++; + return 0; + } + } + + for (i = 0; i < count; i++) { + s32 retcode; + + retcode = qcafrm_fsm_decode(&qca->frm_handle, + qca->rx_skb->data, + skb_tailroom(qca->rx_skb), + data[i]); + + switch (retcode) { + case QCAFRM_GATHER: + case QCAFRM_NOHEAD: + break; + case QCAFRM_NOTAIL: + netdev_dbg(netdev, "recv: no RX tail\n"); + n_stats->rx_errors++; + n_stats->rx_dropped++; + break; + case QCAFRM_INVLEN: + netdev_dbg(netdev, "recv: invalid RX length\n"); + n_stats->rx_errors++; + n_stats->rx_dropped++; + break; + default: + n_stats->rx_packets++; + n_stats->rx_bytes += retcode; + skb_put(qca->rx_skb, retcode); + qca->rx_skb->protocol = eth_type_trans( + qca->rx_skb, qca->rx_skb->dev); + qca->rx_skb->ip_summed = CHECKSUM_UNNECESSARY; + netif_rx_ni(qca->rx_skb); + qca->rx_skb = netdev_alloc_skb_ip_align(netdev, + netdev->mtu + + VLAN_ETH_HLEN); + if (!qca->rx_skb) { + netdev_dbg(netdev, "recv: out of RX resources\n"); + n_stats->rx_errors++; + return i; + } + } + } + + return i; +} + +/* Write out any remaining transmit buffer. Scheduled when tty is writable */ +static void qcauart_transmit(struct work_struct *work) +{ + struct qcauart *qca = container_of(work, struct qcauart, tx_work); + struct net_device_stats *n_stats = &qca->net_dev->stats; + int written; + + spin_lock_bh(&qca->lock); + + /* First make sure we're connected. */ + if (!netif_running(qca->net_dev)) { + spin_unlock_bh(&qca->lock); + return; + } + + if (qca->tx_left <= 0) { + /* Now serial buffer is almost free & we can start + * transmission of another packet + */ + n_stats->tx_packets++; + spin_unlock_bh(&qca->lock); + netif_wake_queue(qca->net_dev); + return; + } + + written = serdev_device_write_buf(qca->serdev, qca->tx_head, + qca->tx_left); + if (written > 0) { + qca->tx_left -= written; + qca->tx_head += written; + } + spin_unlock_bh(&qca->lock); +} + +/* Called by the driver when there's room for more data. + * Schedule the transmit. + */ +static void qca_tty_wakeup(struct serdev_device *serdev) +{ + struct qcauart *qca = serdev_device_get_drvdata(serdev); + + schedule_work(&qca->tx_work); +} + +static struct serdev_device_ops qca_serdev_ops = { + .receive_buf = qca_tty_receive, + .write_wakeup = qca_tty_wakeup, +}; + +static int qcauart_netdev_open(struct net_device *dev) +{ + struct qcauart *qca = netdev_priv(dev); + + netif_start_queue(qca->net_dev); + + return 0; +} + +static int qcauart_netdev_close(struct net_device *dev) +{ + struct qcauart *qca = netdev_priv(dev); + + netif_stop_queue(dev); + flush_work(&qca->tx_work); + + spin_lock_bh(&qca->lock); + qca->tx_left = 0; + spin_unlock_bh(&qca->lock); + + return 0; +} + +static netdev_tx_t +qcauart_netdev_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct net_device_stats *n_stats = &dev->stats; + struct qcauart *qca = netdev_priv(dev); + u8 pad_len = 0; + int written; + u8 *pos; + + spin_lock(&qca->lock); + + WARN_ON(qca->tx_left); + + if (!netif_running(dev)) { + spin_unlock(&qca->lock); + netdev_warn(qca->net_dev, "xmit: iface is down\n"); + goto out; + } + + pos = qca->tx_buffer; + + if (skb->len < QCAFRM_MIN_LEN) + pad_len = QCAFRM_MIN_LEN - skb->len; + + pos += qcafrm_create_header(pos, skb->len + pad_len); + + memcpy(pos, skb->data, skb->len); + pos += skb->len; + + if (pad_len) { + memset(pos, 0, pad_len); + pos += pad_len; + } + + pos += qcafrm_create_footer(pos); + + netif_stop_queue(qca->net_dev); + + written = serdev_device_write_buf(qca->serdev, qca->tx_buffer, + pos - qca->tx_buffer); + if (written > 0) { + qca->tx_left = (pos - qca->tx_buffer) - written; + qca->tx_head = qca->tx_buffer + written; + n_stats->tx_bytes += written; + } + spin_unlock(&qca->lock); + + netif_trans_update(dev); +out: + dev_kfree_skb_any(skb); + return NETDEV_TX_OK; +} + +static void qcauart_netdev_tx_timeout(struct net_device *dev) +{ + struct qcauart *qca = netdev_priv(dev); + + netdev_info(qca->net_dev, "Transmit timeout at %ld, latency %ld\n", + jiffies, dev_trans_start(dev)); + dev->stats.tx_errors++; + dev->stats.tx_dropped++; +} + +static int qcauart_netdev_init(struct net_device *dev) +{ + struct qcauart *qca = netdev_priv(dev); + size_t len; + + /* Finish setting up the device info. */ + dev->mtu = QCAFRM_MAX_MTU; + dev->type = ARPHRD_ETHER; + + len = QCAFRM_HEADER_LEN + QCAFRM_MAX_LEN + QCAFRM_FOOTER_LEN; + qca->tx_buffer = devm_kmalloc(&qca->serdev->dev, len, GFP_KERNEL); + if (!qca->tx_buffer) + return -ENOMEM; + + qca->rx_skb = netdev_alloc_skb_ip_align(qca->net_dev, + qca->net_dev->mtu + + VLAN_ETH_HLEN); + if (!qca->rx_skb) + return -ENOBUFS; + + return 0; +} + +static void qcauart_netdev_uninit(struct net_device *dev) +{ + struct qcauart *qca = netdev_priv(dev); + + if (qca->rx_skb) + dev_kfree_skb(qca->rx_skb); +} + +static const struct net_device_ops qcauart_netdev_ops = { + .ndo_init = qcauart_netdev_init, + .ndo_uninit = qcauart_netdev_uninit, + .ndo_open = qcauart_netdev_open, + .ndo_stop = qcauart_netdev_close, + .ndo_start_xmit = qcauart_netdev_xmit, + .ndo_set_mac_address = eth_mac_addr, + .ndo_tx_timeout = qcauart_netdev_tx_timeout, + .ndo_validate_addr = eth_validate_addr, +}; + +static void qcauart_netdev_setup(struct net_device *dev) +{ + dev->netdev_ops = &qcauart_netdev_ops; + dev->watchdog_timeo = QCAUART_TX_TIMEOUT; + dev->priv_flags &= ~IFF_TX_SKB_SHARING; + dev->tx_queue_len = 100; + + /* MTU range: 46 - 1500 */ + dev->min_mtu = QCAFRM_MIN_MTU; + dev->max_mtu = QCAFRM_MAX_MTU; +} + +static const struct of_device_id qca_uart_of_match[] = { + { + .compatible = "qca,qca7000", + }, + {} +}; +MODULE_DEVICE_TABLE(of, qca_uart_of_match); + +static int qca_uart_probe(struct serdev_device *serdev) +{ + struct net_device *qcauart_dev = alloc_etherdev(sizeof(struct qcauart)); + struct qcauart *qca; + const char *mac; + u32 speed = 115200; + int ret; + + if (!qcauart_dev) + return -ENOMEM; + + qcauart_netdev_setup(qcauart_dev); + SET_NETDEV_DEV(qcauart_dev, &serdev->dev); + + qca = netdev_priv(qcauart_dev); + if (!qca) { + pr_err("qca_uart: Fail to retrieve private structure\n"); + ret = -ENOMEM; + goto free; + } + qca->net_dev = qcauart_dev; + qca->serdev = serdev; + qcafrm_fsm_init_uart(&qca->frm_handle); + + spin_lock_init(&qca->lock); + INIT_WORK(&qca->tx_work, qcauart_transmit); + + of_property_read_u32(serdev->dev.of_node, "current-speed", &speed); + + mac = of_get_mac_address(serdev->dev.of_node); + + if (mac) + ether_addr_copy(qca->net_dev->dev_addr, mac); + + if (!is_valid_ether_addr(qca->net_dev->dev_addr)) { + eth_hw_addr_random(qca->net_dev); + dev_info(&serdev->dev, "Using random MAC address: %pM\n", + qca->net_dev->dev_addr); + } + + netif_carrier_on(qca->net_dev); + serdev_device_set_drvdata(serdev, qca); + serdev_device_set_client_ops(serdev, &qca_serdev_ops); + + ret = serdev_device_open(serdev); + if (ret) { + dev_err(&serdev->dev, "Unable to open device %s\n", + qcauart_dev->name); + goto free; + } + + speed = serdev_device_set_baudrate(serdev, speed); + dev_info(&serdev->dev, "Using baudrate: %u\n", speed); + + serdev_device_set_flow_control(serdev, false); + + ret = register_netdev(qcauart_dev); + if (ret) { + dev_err(&serdev->dev, "Unable to register net device %s\n", + qcauart_dev->name); + serdev_device_close(serdev); + cancel_work_sync(&qca->tx_work); + goto free; + } + + return 0; + +free: + free_netdev(qcauart_dev); + return ret; +} + +static void qca_uart_remove(struct serdev_device *serdev) +{ + struct qcauart *qca = serdev_device_get_drvdata(serdev); + + unregister_netdev(qca->net_dev); + + /* Flush any pending characters in the driver. */ + serdev_device_close(serdev); + cancel_work_sync(&qca->tx_work); + + free_netdev(qca->net_dev); +} + +static struct serdev_device_driver qca_uart_driver = { + .probe = qca_uart_probe, + .remove = qca_uart_remove, + .driver = { + .name = QCAUART_DRV_NAME, + .of_match_table = of_match_ptr(qca_uart_of_match), + }, +}; + +module_serdev_device_driver(qca_uart_driver); + +MODULE_DESCRIPTION("Qualcomm Atheros QCA7000 UART Driver"); +MODULE_AUTHOR("Qualcomm Atheros Communications"); +MODULE_AUTHOR("Stefan Wahren "); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_VERSION(QCAUART_DRV_VERSION);