--- /dev/null
+/*
+ * netup_unidvb_i2c.c
+ *
+ * Internal I2C bus driver for NetUP Universal Dual DVB-CI
+ *
+ * Copyright (C) 2014 NetUP Inc.
+ * Copyright (C) 2014 Sergey Kozlov <serjk@netup.ru>
+ * Copyright (C) 2014 Abylay Ospan <aospan@netup.ru>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include "netup_unidvb.h"
+
+#define NETUP_I2C_BUS0_ADDR 0x4800
+#define NETUP_I2C_BUS1_ADDR 0x4840
+#define NETUP_I2C_TIMEOUT 1000
+
+/* twi_ctrl0_stat reg bits */
+#define TWI_IRQEN_COMPL 0x1
+#define TWI_IRQEN_ANACK 0x2
+#define TWI_IRQEN_DNACK 0x4
+#define TWI_IRQ_COMPL (TWI_IRQEN_COMPL << 8)
+#define TWI_IRQ_ANACK (TWI_IRQEN_ANACK << 8)
+#define TWI_IRQ_DNACK (TWI_IRQEN_DNACK << 8)
+#define TWI_IRQ_TX 0x800
+#define TWI_IRQ_RX 0x1000
+#define TWI_IRQEN (TWI_IRQEN_COMPL | TWI_IRQEN_ANACK | TWI_IRQEN_DNACK)
+/* twi_addr_ctrl1 reg bits*/
+#define TWI_TRANSFER 0x100
+#define TWI_NOSTOP 0x200
+#define TWI_SOFT_RESET 0x2000
+/* twi_clkdiv reg value */
+#define TWI_CLKDIV 156
+/* fifo_stat_ctrl reg bits */
+#define FIFO_IRQEN 0x8000
+#define FIFO_RESET 0x4000
+/* FIFO size */
+#define FIFO_SIZE 16
+
+struct netup_i2c_fifo_regs {
+ union {
+ __u8 data8;
+ __le16 data16;
+ __le32 data32;
+ };
+ __u8 padding[4];
+ __le16 stat_ctrl;
+} __packed __aligned(1);
+
+struct netup_i2c_regs {
+ __le16 clkdiv;
+ __le16 twi_ctrl0_stat;
+ __le16 twi_addr_ctrl1;
+ __le16 length;
+ __u8 padding1[8];
+ struct netup_i2c_fifo_regs tx_fifo;
+ __u8 padding2[6];
+ struct netup_i2c_fifo_regs rx_fifo;
+} __packed __aligned(1);
+
+irqreturn_t netup_i2c_interrupt(struct netup_i2c *i2c)
+{
+ u16 reg, tmp;
+ unsigned long flags;
+ irqreturn_t iret = IRQ_HANDLED;
+
+ spin_lock_irqsave(&i2c->lock, flags);
+ reg = readw(&i2c->regs->twi_ctrl0_stat);
+ writew(reg & ~TWI_IRQEN, &i2c->regs->twi_ctrl0_stat);
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): twi_ctrl0_state 0x%x\n", __func__, reg);
+ if ((reg & TWI_IRQEN_COMPL) != 0 && (reg & TWI_IRQ_COMPL)) {
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): TWI_IRQEN_COMPL\n", __func__);
+ i2c->state = STATE_DONE;
+ goto irq_ok;
+ }
+ if ((reg & TWI_IRQEN_ANACK) != 0 && (reg & TWI_IRQ_ANACK)) {
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): TWI_IRQEN_ANACK\n", __func__);
+ i2c->state = STATE_ERROR;
+ goto irq_ok;
+ }
+ if ((reg & TWI_IRQEN_DNACK) != 0 && (reg & TWI_IRQ_DNACK)) {
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): TWI_IRQEN_DNACK\n", __func__);
+ i2c->state = STATE_ERROR;
+ goto irq_ok;
+ }
+ if ((reg & TWI_IRQ_RX) != 0) {
+ tmp = readw(&i2c->regs->rx_fifo.stat_ctrl);
+ writew(tmp & ~FIFO_IRQEN, &i2c->regs->rx_fifo.stat_ctrl);
+ i2c->state = STATE_WANT_READ;
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): want read\n", __func__);
+ goto irq_ok;
+ }
+ if ((reg & TWI_IRQ_TX) != 0) {
+ tmp = readw(&i2c->regs->tx_fifo.stat_ctrl);
+ writew(tmp & ~FIFO_IRQEN, &i2c->regs->tx_fifo.stat_ctrl);
+ i2c->state = STATE_WANT_WRITE;
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): want write\n", __func__);
+ goto irq_ok;
+ }
+ dev_warn(&i2c->adap.dev, "%s(): not mine interrupt\n", __func__);
+ iret = IRQ_NONE;
+irq_ok:
+ spin_unlock_irqrestore(&i2c->lock, flags);
+ if (iret == IRQ_HANDLED)
+ wake_up(&i2c->wq);
+ return iret;
+}
+
+static void netup_i2c_reset(struct netup_i2c *i2c)
+{
+ dev_dbg(i2c->adap.dev.parent, "%s()\n", __func__);
+ i2c->state = STATE_DONE;
+ writew(TWI_SOFT_RESET, &i2c->regs->twi_addr_ctrl1);
+ writew(TWI_CLKDIV, &i2c->regs->clkdiv);
+ writew(FIFO_RESET, &i2c->regs->tx_fifo.stat_ctrl);
+ writew(FIFO_RESET, &i2c->regs->rx_fifo.stat_ctrl);
+ writew(0x800, &i2c->regs->tx_fifo.stat_ctrl);
+ writew(0x800, &i2c->regs->rx_fifo.stat_ctrl);
+}
+
+static void netup_i2c_fifo_tx(struct netup_i2c *i2c)
+{
+ u8 data;
+ u32 fifo_space = FIFO_SIZE -
+ (readw(&i2c->regs->tx_fifo.stat_ctrl) & 0x3f);
+ u32 msg_length = i2c->msg->len - i2c->xmit_size;
+
+ msg_length = (msg_length < fifo_space ? msg_length : fifo_space);
+ while (msg_length--) {
+ data = i2c->msg->buf[i2c->xmit_size++];
+ writeb(data, &i2c->regs->tx_fifo.data8);
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): write 0x%02x\n", __func__, data);
+ }
+ if (i2c->xmit_size < i2c->msg->len) {
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): TX IRQ enabled\n", __func__);
+ writew(readw(&i2c->regs->tx_fifo.stat_ctrl) | FIFO_IRQEN,
+ &i2c->regs->tx_fifo.stat_ctrl);
+ }
+}
+
+static void netup_i2c_fifo_rx(struct netup_i2c *i2c)
+{
+ u8 data;
+ u32 fifo_size = readw(&i2c->regs->rx_fifo.stat_ctrl) & 0x3f;
+
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): RX fifo size %d\n", __func__, fifo_size);
+ while (fifo_size--) {
+ data = readb(&i2c->regs->rx_fifo.data8);
+ if ((i2c->msg->flags & I2C_M_RD) != 0 &&
+ i2c->xmit_size < i2c->msg->len) {
+ i2c->msg->buf[i2c->xmit_size++] = data;
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): read 0x%02x\n", __func__, data);
+ }
+ }
+ if (i2c->xmit_size < i2c->msg->len) {
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): RX IRQ enabled\n", __func__);
+ writew(readw(&i2c->regs->rx_fifo.stat_ctrl) | FIFO_IRQEN,
+ &i2c->regs->rx_fifo.stat_ctrl);
+ }
+}
+
+static void netup_i2c_start_xfer(struct netup_i2c *i2c)
+{
+ u16 rdflag = ((i2c->msg->flags & I2C_M_RD) ? 1 : 0);
+ u16 reg = readw(&i2c->regs->twi_ctrl0_stat);
+
+ writew(TWI_IRQEN | reg, &i2c->regs->twi_ctrl0_stat);
+ writew(i2c->msg->len, &i2c->regs->length);
+ writew(TWI_TRANSFER | (i2c->msg->addr << 1) | rdflag,
+ &i2c->regs->twi_addr_ctrl1);
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): length %d twi_addr_ctrl1 0x%x twi_ctrl0_stat 0x%x\n",
+ __func__, readw(&i2c->regs->length),
+ readw(&i2c->regs->twi_addr_ctrl1),
+ readw(&i2c->regs->twi_ctrl0_stat));
+ i2c->state = STATE_WAIT;
+ i2c->xmit_size = 0;
+ if (!rdflag)
+ netup_i2c_fifo_tx(i2c);
+ else
+ writew(FIFO_IRQEN | readw(&i2c->regs->rx_fifo.stat_ctrl),
+ &i2c->regs->rx_fifo.stat_ctrl);
+}
+
+static int netup_i2c_xfer(struct i2c_adapter *adap,
+ struct i2c_msg *msgs, int num)
+{
+ unsigned long flags;
+ int i, trans_done, res = num;
+ struct netup_i2c *i2c = i2c_get_adapdata(adap);
+ u16 reg;
+
+ if (num <= 0) {
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): num == %d\n", __func__, num);
+ return -EINVAL;
+ }
+ spin_lock_irqsave(&i2c->lock, flags);
+ if (i2c->state != STATE_DONE) {
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): i2c->state == %d, resetting I2C\n",
+ __func__, i2c->state);
+ netup_i2c_reset(i2c);
+ }
+ dev_dbg(i2c->adap.dev.parent, "%s() num %d\n", __func__, num);
+ for (i = 0; i < num; i++) {
+ i2c->msg = &msgs[i];
+ netup_i2c_start_xfer(i2c);
+ trans_done = 0;
+ while (!trans_done) {
+ spin_unlock_irqrestore(&i2c->lock, flags);
+ if (wait_event_timeout(i2c->wq,
+ i2c->state != STATE_WAIT,
+ msecs_to_jiffies(NETUP_I2C_TIMEOUT))) {
+ spin_lock_irqsave(&i2c->lock, flags);
+ switch (i2c->state) {
+ case STATE_WANT_READ:
+ netup_i2c_fifo_rx(i2c);
+ break;
+ case STATE_WANT_WRITE:
+ netup_i2c_fifo_tx(i2c);
+ break;
+ case STATE_DONE:
+ if ((i2c->msg->flags & I2C_M_RD) != 0 &&
+ i2c->xmit_size != i2c->msg->len)
+ netup_i2c_fifo_rx(i2c);
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): msg %d OK\n",
+ __func__, i);
+ trans_done = 1;
+ break;
+ case STATE_ERROR:
+ res = -EIO;
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): error state\n",
+ __func__);
+ goto done;
+ default:
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): invalid state %d\n",
+ __func__, i2c->state);
+ res = -EINVAL;
+ goto done;
+ }
+ if (!trans_done) {
+ i2c->state = STATE_WAIT;
+ reg = readw(
+ &i2c->regs->twi_ctrl0_stat);
+ writew(TWI_IRQEN | reg,
+ &i2c->regs->twi_ctrl0_stat);
+ }
+ spin_unlock_irqrestore(&i2c->lock, flags);
+ } else {
+ spin_lock_irqsave(&i2c->lock, flags);
+ dev_dbg(i2c->adap.dev.parent,
+ "%s(): wait timeout\n", __func__);
+ res = -ETIMEDOUT;
+ goto done;
+ }
+ spin_lock_irqsave(&i2c->lock, flags);
+ }
+ }
+done:
+ spin_unlock_irqrestore(&i2c->lock, flags);
+ dev_dbg(i2c->adap.dev.parent, "%s(): result %d\n", __func__, res);
+ return res;
+}
+
+static u32 netup_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm netup_i2c_algorithm = {
+ .master_xfer = netup_i2c_xfer,
+ .functionality = netup_i2c_func,
+};
+
+static struct i2c_adapter netup_i2c_adapter = {
+ .owner = THIS_MODULE,
+ .name = NETUP_UNIDVB_NAME,
+ .class = I2C_CLASS_HWMON | I2C_CLASS_SPD,
+ .algo = &netup_i2c_algorithm,
+};
+
+static int netup_i2c_init(struct netup_unidvb_dev *ndev, int bus_num)
+{
+ int ret;
+ struct netup_i2c *i2c;
+
+ if (bus_num < 0 || bus_num > 1) {
+ dev_err(&ndev->pci_dev->dev,
+ "%s(): invalid bus_num %d\n", __func__, bus_num);
+ return -EINVAL;
+ }
+ i2c = &ndev->i2c[bus_num];
+ spin_lock_init(&i2c->lock);
+ init_waitqueue_head(&i2c->wq);
+ i2c->regs = (struct netup_i2c_regs __iomem *)(ndev->bmmio0 +
+ (bus_num == 0 ? NETUP_I2C_BUS0_ADDR : NETUP_I2C_BUS1_ADDR));
+ netup_i2c_reset(i2c);
+ i2c->adap = netup_i2c_adapter;
+ i2c->adap.dev.parent = &ndev->pci_dev->dev;
+ i2c_set_adapdata(&i2c->adap, i2c);
+ ret = i2c_add_adapter(&i2c->adap);
+ if (ret) {
+ dev_err(&ndev->pci_dev->dev,
+ "%s(): failed to add I2C adapter\n", __func__);
+ return ret;
+ }
+ dev_info(&ndev->pci_dev->dev,
+ "%s(): registered I2C bus %d at 0x%x\n",
+ __func__,
+ bus_num, (bus_num == 0 ?
+ NETUP_I2C_BUS0_ADDR :
+ NETUP_I2C_BUS1_ADDR));
+ return 0;
+}
+
+static void netup_i2c_remove(struct netup_unidvb_dev *ndev, int bus_num)
+{
+ struct netup_i2c *i2c;
+
+ if (bus_num < 0 || bus_num > 1) {
+ dev_err(&ndev->pci_dev->dev,
+ "%s(): invalid bus number %d\n", __func__, bus_num);
+ return;
+ }
+ i2c = &ndev->i2c[bus_num];
+ netup_i2c_reset(i2c);
+ /* remove adapter */
+ i2c_del_adapter(&i2c->adap);
+ dev_info(&ndev->pci_dev->dev,
+ "netup_i2c_remove: unregistered I2C bus %d\n", bus_num);
+}
+
+int netup_i2c_register(struct netup_unidvb_dev *ndev)
+{
+ int ret;
+
+ ret = netup_i2c_init(ndev, 0);
+ if (ret)
+ return ret;
+ ret = netup_i2c_init(ndev, 1);
+ if (ret) {
+ netup_i2c_remove(ndev, 0);
+ return ret;
+ }
+ return 0;
+}
+
+void netup_i2c_unregister(struct netup_unidvb_dev *ndev)
+{
+ netup_i2c_remove(ndev, 0);
+ netup_i2c_remove(ndev, 1);
+}
+
Code Review / kvmfornfv.git / blobdiff