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authorVincent Cuissard <cuissard@marvell.com>2015-06-11 12:25:46 +0300
committerSamuel Ortiz <sameo@linux.intel.com>2015-06-12 00:25:21 +0300
commit4a2b947f56b33cde68d6e0543160ea09ce651fd9 (patch)
tree5bd042492e6be12b7d9d8320012bb414b0d339fb /drivers
parent8a81a96bd116ef5c505f37e035ce141f6b35a6a7 (diff)
downloadlinux-4a2b947f56b33cde68d6e0543160ea09ce651fd9.tar.xz
NFC: nfcmrvl: add chip reset management
Low level driver can specify a GPIO that will be used to reset the chip. Thanks to this the driver can ensure the state of the device at init. Signed-off-by: Vincent Cuissard <cuissard@marvell.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/nfc/nfcmrvl/main.c30
-rw-r--r--drivers/nfc/nfcmrvl/nfcmrvl.h8
2 files changed, 38 insertions, 0 deletions
diff --git a/drivers/nfc/nfcmrvl/main.c b/drivers/nfc/nfcmrvl/main.c
index e7f579b2d987..708aad28c567 100644
--- a/drivers/nfc/nfcmrvl/main.c
+++ b/drivers/nfc/nfcmrvl/main.c
@@ -17,6 +17,8 @@
*/
#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
#include <linux/nfc.h>
#include <net/nfc/nci.h>
#include <net/nfc/nci_core.h>
@@ -107,6 +109,16 @@ struct nfcmrvl_private *nfcmrvl_nci_register_dev(void *drv_data,
priv->if_ops = ops;
priv->dev = dev;
priv->hci_muxed = (flags & NFCMRVL_DEV_FLAG_HCI_MUXED) ? 1 : 0;
+ priv->reset_n_io = NFCMRVL_DEV_FLAG_GET_RESET_N_IO(flags);
+
+ if (priv->reset_n_io) {
+ rc = devm_gpio_request_one(dev,
+ priv->reset_n_io,
+ GPIOF_OUT_INIT_LOW,
+ "nfcmrvl_reset_n");
+ if (rc < 0)
+ nfc_err(dev, "failed to request reset_n io\n");
+ }
if (priv->hci_muxed)
headroom = NFCMRVL_HCI_EVENT_HEADER_SIZE;
@@ -127,6 +139,8 @@ struct nfcmrvl_private *nfcmrvl_nci_register_dev(void *drv_data,
nci_set_drvdata(priv->ndev, priv);
+ nfcmrvl_chip_reset(priv);
+
rc = nci_register_device(priv->ndev);
if (rc) {
nfc_err(dev, "nci_register_device failed %d\n", rc);
@@ -179,6 +193,22 @@ int nfcmrvl_nci_recv_frame(struct nfcmrvl_private *priv, struct sk_buff *skb)
}
EXPORT_SYMBOL_GPL(nfcmrvl_nci_recv_frame);
+void nfcmrvl_chip_reset(struct nfcmrvl_private *priv)
+{
+ /*
+ * This function does not take care if someone is using the device.
+ * To be improved.
+ */
+
+ if (priv->reset_n_io) {
+ nfc_info(priv->dev, "reset the chip\n");
+ gpio_set_value(priv->reset_n_io, 0);
+ usleep_range(5000, 10000);
+ gpio_set_value(priv->reset_n_io, 1);
+ } else
+ nfc_info(priv->dev, "no reset available on this interface\n");
+}
+
MODULE_AUTHOR("Marvell International Ltd.");
MODULE_DESCRIPTION("Marvell NFC driver ver " VERSION);
MODULE_VERSION(VERSION);
diff --git a/drivers/nfc/nfcmrvl/nfcmrvl.h b/drivers/nfc/nfcmrvl/nfcmrvl.h
index 7a10dabaf1b2..2edae9a4b6bd 100644
--- a/drivers/nfc/nfcmrvl/nfcmrvl.h
+++ b/drivers/nfc/nfcmrvl/nfcmrvl.h
@@ -39,12 +39,18 @@
#define NFCMRVL_HCI_OCF 0xFE
#define NFCMRVL_DEV_FLAG_HCI_MUXED (1 << 0)
+#define NFCMRVL_DEV_FLAG_SET_RESET_N_IO(X) ((X) << 16)
+#define NFCMRVL_DEV_FLAG_GET_RESET_N_IO(X) ((X) >> 16)
struct nfcmrvl_private {
/* Tell if NCI packets are encapsulated in HCI ones */
int hci_muxed;
struct nci_dev *ndev;
+
+ /* Reset IO (0 if not available) */
+ int reset_n_io;
+
unsigned long flags;
void *drv_data;
struct device *dev;
@@ -63,3 +69,5 @@ struct nfcmrvl_private *nfcmrvl_nci_register_dev(void *drv_data,
struct nfcmrvl_if_ops *ops,
struct device *dev,
unsigned int flags);
+
+void nfcmrvl_chip_reset(struct nfcmrvl_private *priv);