diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-s6000.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-s6000.c | 404 |
1 files changed, 0 insertions, 404 deletions
diff --git a/drivers/i2c/busses/i2c-s6000.c b/drivers/i2c/busses/i2c-s6000.c deleted file mode 100644 index dd186a037684..000000000000 --- a/drivers/i2c/busses/i2c-s6000.c +++ /dev/null @@ -1,404 +0,0 @@ -/* - * drivers/i2c/busses/i2c-s6000.c - * - * Description: Driver for S6000 Family I2C Interface - * Copyright (c) 2008 emlix GmbH - * Author: Oskar Schirmer <oskar@scara.com> - * - * Partially based on i2c-bfin-twi.c driver by <sonic.zhang@analog.com> - * Copyright (c) 2005-2007 Analog Devices, Inc. - * - * 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. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA - */ - -#include <linux/clk.h> -#include <linux/err.h> -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/init.h> -#include <linux/delay.h> -#include <linux/i2c.h> -#include <linux/i2c/s6000.h> -#include <linux/timer.h> -#include <linux/spinlock.h> -#include <linux/completion.h> -#include <linux/interrupt.h> -#include <linux/platform_device.h> -#include <linux/io.h> - -#include "i2c-s6000.h" - -#define DRV_NAME "i2c-s6000" - -#define POLL_TIMEOUT (2 * HZ) - -struct s6i2c_if { - u8 __iomem *reg; /* memory mapped registers */ - int irq; - spinlock_t lock; - struct i2c_msg *msgs; /* messages currently handled */ - int msgs_num; /* nb of msgs to do */ - int msgs_push; /* nb of msgs read/written */ - int msgs_done; /* nb of msgs finally handled */ - unsigned push; /* nb of bytes read/written in msg */ - unsigned done; /* nb of bytes finally handled */ - int timeout_count; /* timeout retries left */ - struct timer_list timeout_timer; - struct i2c_adapter adap; - struct completion complete; - struct clk *clk; - struct resource *res; -}; - -static inline u16 i2c_rd16(struct s6i2c_if *iface, unsigned n) -{ - return readw(iface->reg + (n)); -} - -static inline void i2c_wr16(struct s6i2c_if *iface, unsigned n, u16 v) -{ - writew(v, iface->reg + (n)); -} - -static inline u32 i2c_rd32(struct s6i2c_if *iface, unsigned n) -{ - return readl(iface->reg + (n)); -} - -static inline void i2c_wr32(struct s6i2c_if *iface, unsigned n, u32 v) -{ - writel(v, iface->reg + (n)); -} - -static struct s6i2c_if s6i2c_if; - -static void s6i2c_handle_interrupt(struct s6i2c_if *iface) -{ - if (i2c_rd16(iface, S6_I2C_INTRSTAT) & (1 << S6_I2C_INTR_TXABRT)) { - i2c_rd16(iface, S6_I2C_CLRTXABRT); - i2c_wr16(iface, S6_I2C_INTRMASK, 0); - complete(&iface->complete); - return; - } - if (iface->msgs_done >= iface->msgs_num) { - dev_err(&iface->adap.dev, "s6i2c: spurious I2C irq: %04x\n", - i2c_rd16(iface, S6_I2C_INTRSTAT)); - i2c_wr16(iface, S6_I2C_INTRMASK, 0); - return; - } - while ((iface->msgs_push < iface->msgs_num) - && (i2c_rd16(iface, S6_I2C_STATUS) & (1 << S6_I2C_STATUS_TFNF))) { - struct i2c_msg *m = &iface->msgs[iface->msgs_push]; - if (!(m->flags & I2C_M_RD)) - i2c_wr16(iface, S6_I2C_DATACMD, m->buf[iface->push]); - else - i2c_wr16(iface, S6_I2C_DATACMD, - 1 << S6_I2C_DATACMD_READ); - if (++iface->push >= m->len) { - iface->push = 0; - iface->msgs_push += 1; - } - } - do { - struct i2c_msg *m = &iface->msgs[iface->msgs_done]; - if (!(m->flags & I2C_M_RD)) { - if (iface->msgs_done < iface->msgs_push) - iface->msgs_done += 1; - else - break; - } else if (i2c_rd16(iface, S6_I2C_STATUS) - & (1 << S6_I2C_STATUS_RFNE)) { - m->buf[iface->done] = i2c_rd16(iface, S6_I2C_DATACMD); - if (++iface->done >= m->len) { - iface->done = 0; - iface->msgs_done += 1; - } - } else{ - break; - } - } while (iface->msgs_done < iface->msgs_num); - if (iface->msgs_done >= iface->msgs_num) { - i2c_wr16(iface, S6_I2C_INTRMASK, 1 << S6_I2C_INTR_TXABRT); - complete(&iface->complete); - } else if (iface->msgs_push >= iface->msgs_num) { - i2c_wr16(iface, S6_I2C_INTRMASK, (1 << S6_I2C_INTR_TXABRT) | - (1 << S6_I2C_INTR_RXFULL)); - } else { - i2c_wr16(iface, S6_I2C_INTRMASK, (1 << S6_I2C_INTR_TXABRT) | - (1 << S6_I2C_INTR_TXEMPTY) | - (1 << S6_I2C_INTR_RXFULL)); - } -} - -static irqreturn_t s6i2c_interrupt_entry(int irq, void *dev_id) -{ - struct s6i2c_if *iface = dev_id; - if (!(i2c_rd16(iface, S6_I2C_STATUS) & ((1 << S6_I2C_INTR_RXUNDER) - | (1 << S6_I2C_INTR_RXOVER) - | (1 << S6_I2C_INTR_RXFULL) - | (1 << S6_I2C_INTR_TXOVER) - | (1 << S6_I2C_INTR_TXEMPTY) - | (1 << S6_I2C_INTR_RDREQ) - | (1 << S6_I2C_INTR_TXABRT) - | (1 << S6_I2C_INTR_RXDONE) - | (1 << S6_I2C_INTR_ACTIVITY) - | (1 << S6_I2C_INTR_STOPDET) - | (1 << S6_I2C_INTR_STARTDET) - | (1 << S6_I2C_INTR_GENCALL)))) - return IRQ_NONE; - - spin_lock(&iface->lock); - del_timer(&iface->timeout_timer); - s6i2c_handle_interrupt(iface); - spin_unlock(&iface->lock); - return IRQ_HANDLED; -} - -static void s6i2c_timeout(unsigned long data) -{ - struct s6i2c_if *iface = (struct s6i2c_if *)data; - unsigned long flags; - - spin_lock_irqsave(&iface->lock, flags); - s6i2c_handle_interrupt(iface); - if (--iface->timeout_count > 0) { - iface->timeout_timer.expires = jiffies + POLL_TIMEOUT; - add_timer(&iface->timeout_timer); - } else { - complete(&iface->complete); - i2c_wr16(iface, S6_I2C_INTRMASK, 0); - } - spin_unlock_irqrestore(&iface->lock, flags); -} - -static int s6i2c_master_xfer(struct i2c_adapter *adap, - struct i2c_msg *msgs, int num) -{ - struct s6i2c_if *iface = adap->algo_data; - int i; - if (num == 0) - return 0; - if (i2c_rd16(iface, S6_I2C_STATUS) & (1 << S6_I2C_STATUS_ACTIVITY)) - yield(); - i2c_wr16(iface, S6_I2C_INTRMASK, 0); - i2c_rd16(iface, S6_I2C_CLRINTR); - for (i = 0; i < num; i++) { - if (msgs[i].flags & I2C_M_TEN) { - dev_err(&adap->dev, - "s6i2c: 10 bits addr not supported\n"); - return -EINVAL; - } - if (msgs[i].len == 0) { - dev_err(&adap->dev, - "s6i2c: zero length message not supported\n"); - return -EINVAL; - } - if (msgs[i].addr != msgs[0].addr) { - dev_err(&adap->dev, - "s6i2c: multiple xfer cannot change target\n"); - return -EINVAL; - } - } - - iface->msgs = msgs; - iface->msgs_num = num; - iface->msgs_push = 0; - iface->msgs_done = 0; - iface->push = 0; - iface->done = 0; - iface->timeout_count = 10; - i2c_wr16(iface, S6_I2C_TAR, msgs[0].addr); - i2c_wr16(iface, S6_I2C_ENABLE, 1); - i2c_wr16(iface, S6_I2C_INTRMASK, (1 << S6_I2C_INTR_TXEMPTY) | - (1 << S6_I2C_INTR_TXABRT)); - - iface->timeout_timer.expires = jiffies + POLL_TIMEOUT; - add_timer(&iface->timeout_timer); - wait_for_completion(&iface->complete); - del_timer_sync(&iface->timeout_timer); - while (i2c_rd32(iface, S6_I2C_TXFLR) > 0) - schedule(); - while (i2c_rd16(iface, S6_I2C_STATUS) & (1 << S6_I2C_STATUS_ACTIVITY)) - schedule(); - - i2c_wr16(iface, S6_I2C_INTRMASK, 0); - i2c_wr16(iface, S6_I2C_ENABLE, 0); - return iface->msgs_done; -} - -static u32 s6i2c_functionality(struct i2c_adapter *adap) -{ - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; -} - -static struct i2c_algorithm s6i2c_algorithm = { - .master_xfer = s6i2c_master_xfer, - .functionality = s6i2c_functionality, -}; - -static u16 nanoseconds_on_clk(struct s6i2c_if *iface, u32 ns) -{ - u32 dividend = ((clk_get_rate(iface->clk) / 1000) * ns) / 1000000; - if (dividend > 0xffff) - return 0xffff; - return dividend; -} - -static int s6i2c_probe(struct platform_device *dev) -{ - struct s6i2c_if *iface = &s6i2c_if; - struct i2c_adapter *p_adap; - const char *clock; - int bus_num, rc; - spin_lock_init(&iface->lock); - init_completion(&iface->complete); - iface->irq = platform_get_irq(dev, 0); - if (iface->irq < 0) { - rc = iface->irq; - goto err_out; - } - iface->res = platform_get_resource(dev, IORESOURCE_MEM, 0); - if (!iface->res) { - rc = -ENXIO; - goto err_out; - } - iface->res = request_mem_region(iface->res->start, - resource_size(iface->res), - dev->dev.bus_id); - if (!iface->res) { - rc = -EBUSY; - goto err_out; - } - iface->reg = ioremap_nocache(iface->res->start, - resource_size(iface->res)); - if (!iface->reg) { - rc = -ENOMEM; - goto err_reg; - } - - clock = 0; - bus_num = -1; - if (dev_get_platdata(&dev->dev)) { - struct s6_i2c_platform_data *pdata = - dev_get_platdata(&dev->dev); - bus_num = pdata->bus_num; - clock = pdata->clock; - } - iface->clk = clk_get(&dev->dev, clock); - if (IS_ERR(iface->clk)) { - rc = PTR_ERR(iface->clk); - goto err_map; - } - rc = clk_enable(iface->clk); - if (rc < 0) - goto err_clk_put; - init_timer(&iface->timeout_timer); - iface->timeout_timer.function = s6i2c_timeout; - iface->timeout_timer.data = (unsigned long)iface; - - p_adap = &iface->adap; - strlcpy(p_adap->name, dev->name, sizeof(p_adap->name)); - p_adap->algo = &s6i2c_algorithm; - p_adap->algo_data = iface; - p_adap->nr = bus_num; - p_adap->class = 0; - p_adap->dev.parent = &dev->dev; - i2c_wr16(iface, S6_I2C_INTRMASK, 0); - rc = request_irq(iface->irq, s6i2c_interrupt_entry, - IRQF_SHARED, dev->name, iface); - if (rc) { - dev_err(&p_adap->dev, "s6i2c: can't get IRQ %d\n", iface->irq); - goto err_clk_dis; - } - - i2c_wr16(iface, S6_I2C_ENABLE, 0); - udelay(1); - i2c_wr32(iface, S6_I2C_SRESET, 1 << S6_I2C_SRESET_IC_SRST); - i2c_wr16(iface, S6_I2C_CLRTXABRT, 1); - i2c_wr16(iface, S6_I2C_CON, - (1 << S6_I2C_CON_MASTER) | - (S6_I2C_CON_SPEED_NORMAL << S6_I2C_CON_SPEED) | - (0 << S6_I2C_CON_10BITSLAVE) | - (0 << S6_I2C_CON_10BITMASTER) | - (1 << S6_I2C_CON_RESTARTENA) | - (1 << S6_I2C_CON_SLAVEDISABLE)); - i2c_wr16(iface, S6_I2C_SSHCNT, nanoseconds_on_clk(iface, 4000)); - i2c_wr16(iface, S6_I2C_SSLCNT, nanoseconds_on_clk(iface, 4700)); - i2c_wr16(iface, S6_I2C_FSHCNT, nanoseconds_on_clk(iface, 600)); - i2c_wr16(iface, S6_I2C_FSLCNT, nanoseconds_on_clk(iface, 1300)); - i2c_wr16(iface, S6_I2C_RXTL, 0); - i2c_wr16(iface, S6_I2C_TXTL, 0); - - platform_set_drvdata(dev, iface); - rc = i2c_add_numbered_adapter(p_adap); - if (rc) - goto err_irq_free; - return 0; - -err_irq_free: - free_irq(iface->irq, iface); -err_clk_dis: - clk_disable(iface->clk); -err_clk_put: - clk_put(iface->clk); -err_map: - iounmap(iface->reg); -err_reg: - release_mem_region(iface->res->start, - resource_size(iface->res)); -err_out: - return rc; -} - -static int s6i2c_remove(struct platform_device *pdev) -{ - struct s6i2c_if *iface = platform_get_drvdata(pdev); - i2c_wr16(iface, S6_I2C_ENABLE, 0); - i2c_del_adapter(&iface->adap); - free_irq(iface->irq, iface); - clk_disable(iface->clk); - clk_put(iface->clk); - iounmap(iface->reg); - release_mem_region(iface->res->start, - resource_size(iface->res)); - return 0; -} - -static struct platform_driver s6i2c_driver = { - .probe = s6i2c_probe, - .remove = s6i2c_remove, - .driver = { - .name = DRV_NAME, - .owner = THIS_MODULE, - }, -}; - -static int __init s6i2c_init(void) -{ - pr_info("I2C: S6000 I2C driver\n"); - return platform_driver_register(&s6i2c_driver); -} - -static void __exit s6i2c_exit(void) -{ - platform_driver_unregister(&s6i2c_driver); -} - -MODULE_DESCRIPTION("I2C-Bus adapter routines for S6000 I2C"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS("platform:" DRV_NAME); - -subsys_initcall(s6i2c_init); -module_exit(s6i2c_exit); |