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>
This commit is contained in:
Vincent Cuissard 2015-06-11 11:25:46 +02:00 committed by Samuel Ortiz
parent 8a81a96bd1
commit 4a2b947f56
2 changed files with 38 additions and 0 deletions

View File

@ -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);

View File

@ -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);