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path: root/drivers/nfc/nfcmrvl/spi.c
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Diffstat (limited to 'drivers/nfc/nfcmrvl/spi.c')
-rw-r--r--drivers/nfc/nfcmrvl/spi.c228
1 files changed, 228 insertions, 0 deletions
diff --git a/drivers/nfc/nfcmrvl/spi.c b/drivers/nfc/nfcmrvl/spi.c
new file mode 100644
index 000000000..a7faa0bcc
--- /dev/null
+++ b/drivers/nfc/nfcmrvl/spi.c
@@ -0,0 +1,228 @@
+/**
+ * Marvell NFC-over-SPI driver: SPI interface related functions
+ *
+ * Copyright (C) 2015, Marvell International Ltd.
+ *
+ * This software file (the "File") is distributed by Marvell International
+ * Ltd. under the terms of the GNU General Public License Version 2, June 1991
+ * (the "License"). You may use, redistribute and/or modify this File in
+ * accordance with the terms and conditions of the License, a copy of which
+ * is available on the worldwide web at
+ * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
+ *
+ * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
+ * ARE EXPRESSLY DISCLAIMED. The License provides additional details about
+ * this warranty disclaimer.
+ **/
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/pm_runtime.h>
+#include <linux/nfc.h>
+#include <linux/gpio.h>
+#include <linux/of_irq.h>
+#include <linux/of_gpio.h>
+#include <net/nfc/nci.h>
+#include <net/nfc/nci_core.h>
+#include <linux/spi/spi.h>
+#include <linux/gpio.h>
+#include "nfcmrvl.h"
+
+#define SPI_WAIT_HANDSHAKE 1
+
+struct nfcmrvl_spi_drv_data {
+ unsigned long flags;
+ struct spi_device *spi;
+ struct nci_spi *nci_spi;
+ struct completion handshake_completion;
+ struct nfcmrvl_private *priv;
+};
+
+static irqreturn_t nfcmrvl_spi_int_irq_thread_fn(int irq, void *drv_data_ptr)
+{
+ struct nfcmrvl_spi_drv_data *drv_data = drv_data_ptr;
+ struct sk_buff *skb;
+
+ /*
+ * Special case where we are waiting for SPI_INT deassertion to start a
+ * transfer.
+ */
+ if (test_and_clear_bit(SPI_WAIT_HANDSHAKE, &drv_data->flags)) {
+ complete(&drv_data->handshake_completion);
+ return IRQ_HANDLED;
+ }
+
+ /* Normal case, SPI_INT deasserted by slave to trigger a master read */
+
+ skb = nci_spi_read(drv_data->nci_spi);
+ if (!skb) {
+ nfc_err(&drv_data->spi->dev, "failed to read spi packet");
+ return IRQ_HANDLED;
+ }
+
+ if (nfcmrvl_nci_recv_frame(drv_data->priv, skb) < 0)
+ nfc_err(&drv_data->spi->dev, "corrupted RX packet");
+
+ return IRQ_HANDLED;
+}
+
+static int nfcmrvl_spi_nci_open(struct nfcmrvl_private *priv)
+{
+ return 0;
+}
+
+static int nfcmrvl_spi_nci_close(struct nfcmrvl_private *priv)
+{
+ return 0;
+}
+
+static int nfcmrvl_spi_nci_send(struct nfcmrvl_private *priv,
+ struct sk_buff *skb)
+{
+ struct nfcmrvl_spi_drv_data *drv_data = priv->drv_data;
+ int err;
+
+ /* Reinit completion for slave handshake */
+ reinit_completion(&drv_data->handshake_completion);
+ set_bit(SPI_WAIT_HANDSHAKE, &drv_data->flags);
+
+ /*
+ * Append a dummy byte at the end of SPI frame. This is due to a
+ * specific DMA implementation in the controller
+ */
+ skb_put(skb, 1);
+
+ /* Send the SPI packet */
+ err = nci_spi_send(drv_data->nci_spi, &drv_data->handshake_completion,
+ skb);
+ if (err != 0) {
+ nfc_err(priv->dev, "spi_send failed %d", err);
+ kfree_skb(skb);
+ }
+ return err;
+}
+
+static void nfcmrvl_spi_nci_update_config(struct nfcmrvl_private *priv,
+ const void *param)
+{
+ struct nfcmrvl_spi_drv_data *drv_data = priv->drv_data;
+ const struct nfcmrvl_fw_spi_config *config = param;
+
+ drv_data->nci_spi->xfer_speed_hz = config->clk;
+}
+
+static struct nfcmrvl_if_ops spi_ops = {
+ .nci_open = nfcmrvl_spi_nci_open,
+ .nci_close = nfcmrvl_spi_nci_close,
+ .nci_send = nfcmrvl_spi_nci_send,
+ .nci_update_config = nfcmrvl_spi_nci_update_config,
+};
+
+static int nfcmrvl_spi_parse_dt(struct device_node *node,
+ struct nfcmrvl_platform_data *pdata)
+{
+ int ret;
+
+ ret = nfcmrvl_parse_dt(node, pdata);
+ if (ret < 0) {
+ pr_err("Failed to get generic entries\n");
+ return ret;
+ }
+
+ ret = irq_of_parse_and_map(node, 0);
+ if (ret < 0) {
+ pr_err("Unable to get irq, error: %d\n", ret);
+ return ret;
+ }
+ pdata->irq = ret;
+
+ return 0;
+}
+
+static int nfcmrvl_spi_probe(struct spi_device *spi)
+{
+ struct nfcmrvl_platform_data *pdata;
+ struct nfcmrvl_platform_data config;
+ struct nfcmrvl_spi_drv_data *drv_data;
+ int ret = 0;
+
+ drv_data = devm_kzalloc(&spi->dev, sizeof(*drv_data), GFP_KERNEL);
+ if (!drv_data)
+ return -ENOMEM;
+
+ drv_data->spi = spi;
+ drv_data->priv = NULL;
+ spi_set_drvdata(spi, drv_data);
+
+ pdata = spi->dev.platform_data;
+
+ if (!pdata && spi->dev.of_node)
+ if (nfcmrvl_spi_parse_dt(spi->dev.of_node, &config) == 0)
+ pdata = &config;
+
+ if (!pdata)
+ return -EINVAL;
+
+ ret = devm_request_threaded_irq(&drv_data->spi->dev, pdata->irq,
+ NULL, nfcmrvl_spi_int_irq_thread_fn,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ "nfcmrvl_spi_int", drv_data);
+ if (ret < 0) {
+ nfc_err(&drv_data->spi->dev, "Unable to register IRQ handler");
+ return -ENODEV;
+ }
+
+ drv_data->priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_SPI,
+ drv_data, &spi_ops,
+ &drv_data->spi->dev,
+ pdata);
+ if (IS_ERR(drv_data->priv))
+ return PTR_ERR(drv_data->priv);
+
+ drv_data->priv->support_fw_dnld = true;
+
+ drv_data->nci_spi = nci_spi_allocate_spi(drv_data->spi, 0, 10,
+ drv_data->priv->ndev);
+
+ /* Init completion for slave handshake */
+ init_completion(&drv_data->handshake_completion);
+ return 0;
+}
+
+static int nfcmrvl_spi_remove(struct spi_device *spi)
+{
+ struct nfcmrvl_spi_drv_data *drv_data = spi_get_drvdata(spi);
+
+ nfcmrvl_nci_unregister_dev(drv_data->priv);
+ return 0;
+}
+
+static const struct of_device_id of_nfcmrvl_spi_match[] = {
+ { .compatible = "marvell,nfc-spi", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, of_nfcmrvl_spi_match);
+
+static const struct spi_device_id nfcmrvl_spi_id_table[] = {
+ { "nfcmrvl_spi", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, nfcmrvl_spi_id_table);
+
+static struct spi_driver nfcmrvl_spi_driver = {
+ .probe = nfcmrvl_spi_probe,
+ .remove = nfcmrvl_spi_remove,
+ .id_table = nfcmrvl_spi_id_table,
+ .driver = {
+ .name = "nfcmrvl_spi",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(of_nfcmrvl_spi_match),
+ },
+};
+
+module_spi_driver(nfcmrvl_spi_driver);
+
+MODULE_AUTHOR("Marvell International Ltd.");
+MODULE_DESCRIPTION("Marvell NFC-over-SPI driver");
+MODULE_LICENSE("GPL v2");