diff options
author | Artem Bityutskiy <Artem.Bityutskiy@nokia.com> | 2011-03-25 18:41:20 +0300 |
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committer | Artem Bityutskiy <Artem.Bityutskiy@nokia.com> | 2011-03-25 18:41:20 +0300 |
commit | 7bf7e370d5919112c223a269462cd0b546903829 (patch) | |
tree | 03ccc715239df14ae168277dbccc9d9cf4d8a2c8 /drivers/mfd/ti-ssp.c | |
parent | 68b1a1e786f29c900fa1c516a402e24f0ece622a (diff) | |
parent | d39dd11c3e6a7af5c20bfac40594db36cf270f42 (diff) | |
download | linux-7bf7e370d5919112c223a269462cd0b546903829.tar.xz |
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into for-linus-1
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6: (9356 commits)
[media] rc: update for bitop name changes
fs: simplify iget & friends
fs: pull inode->i_lock up out of writeback_single_inode
fs: rename inode_lock to inode_hash_lock
fs: move i_wb_list out from under inode_lock
fs: move i_sb_list out from under inode_lock
fs: remove inode_lock from iput_final and prune_icache
fs: Lock the inode LRU list separately
fs: factor inode disposal
fs: protect inode->i_state with inode->i_lock
lib, arch: add filter argument to show_mem and fix private implementations
SLUB: Write to per cpu data when allocating it
slub: Fix debugobjects with lockless fastpath
autofs4: Do not potentially dereference NULL pointer returned by fget() in autofs_dev_ioctl_setpipefd()
autofs4 - remove autofs4_lock
autofs4 - fix d_manage() return on rcu-walk
autofs4 - fix autofs4_expire_indirect() traversal
autofs4 - fix dentry leak in autofs4_expire_direct()
autofs4 - reinstate last used update on access
vfs - check non-mountpoint dentry might block in __follow_mount_rcu()
...
NOTE!
This merge commit was created to fix compilation error. The block
tree was merged upstream and removed the 'elv_queue_empty()'
function which the new 'mtdswap' driver is using. So a simple
merge of the mtd tree with upstream does not compile. And the
mtd tree has already be published, so re-basing it is not an option.
To fix this unfortunate situation, I had to merge upstream into the
mtd-2.6.git tree without committing, put the fixup patch on top of
this, and then commit this. The result is that we do not have commits
which do not compile.
In other words, this merge commit "merges" 3 things: the MTD tree, the
upstream tree, and the fixup patch.
Diffstat (limited to 'drivers/mfd/ti-ssp.c')
-rw-r--r-- | drivers/mfd/ti-ssp.c | 476 |
1 files changed, 476 insertions, 0 deletions
diff --git a/drivers/mfd/ti-ssp.c b/drivers/mfd/ti-ssp.c new file mode 100644 index 000000000000..af9ab0e5ca64 --- /dev/null +++ b/drivers/mfd/ti-ssp.c @@ -0,0 +1,476 @@ +/* + * Sequencer Serial Port (SSP) driver for Texas Instruments' SoCs + * + * Copyright (C) 2010 Texas Instruments 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/wait.h> +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/device.h> +#include <linux/spinlock.h> +#include <linux/platform_device.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/mfd/core.h> +#include <linux/mfd/ti_ssp.h> + +/* Register Offsets */ +#define REG_REV 0x00 +#define REG_IOSEL_1 0x04 +#define REG_IOSEL_2 0x08 +#define REG_PREDIV 0x0c +#define REG_INTR_ST 0x10 +#define REG_INTR_EN 0x14 +#define REG_TEST_CTRL 0x18 + +/* Per port registers */ +#define PORT_CFG_2 0x00 +#define PORT_ADDR 0x04 +#define PORT_DATA 0x08 +#define PORT_CFG_1 0x0c +#define PORT_STATE 0x10 + +#define SSP_PORT_CONFIG_MASK (SSP_EARLY_DIN | SSP_DELAY_DOUT) +#define SSP_PORT_CLKRATE_MASK 0x0f + +#define SSP_SEQRAM_WR_EN BIT(4) +#define SSP_SEQRAM_RD_EN BIT(5) +#define SSP_START BIT(15) +#define SSP_BUSY BIT(10) +#define SSP_PORT_ASL BIT(7) +#define SSP_PORT_CFO1 BIT(6) + +#define SSP_PORT_SEQRAM_SIZE 32 + +static const int ssp_port_base[] = {0x040, 0x080}; +static const int ssp_port_seqram[] = {0x100, 0x180}; + +struct ti_ssp { + struct resource *res; + struct device *dev; + void __iomem *regs; + spinlock_t lock; + struct clk *clk; + int irq; + wait_queue_head_t wqh; + + /* + * Some of the iosel2 register bits always read-back as 0, we need to + * remember these values so that we don't clobber previously set + * values. + */ + u32 iosel2; +}; + +static inline struct ti_ssp *dev_to_ssp(struct device *dev) +{ + return dev_get_drvdata(dev->parent); +} + +static inline int dev_to_port(struct device *dev) +{ + return to_platform_device(dev)->id; +} + +/* Register Access Helpers, rmw() functions need to run locked */ +static inline u32 ssp_read(struct ti_ssp *ssp, int reg) +{ + return __raw_readl(ssp->regs + reg); +} + +static inline void ssp_write(struct ti_ssp *ssp, int reg, u32 val) +{ + __raw_writel(val, ssp->regs + reg); +} + +static inline void ssp_rmw(struct ti_ssp *ssp, int reg, u32 mask, u32 bits) +{ + ssp_write(ssp, reg, (ssp_read(ssp, reg) & ~mask) | bits); +} + +static inline u32 ssp_port_read(struct ti_ssp *ssp, int port, int reg) +{ + return ssp_read(ssp, ssp_port_base[port] + reg); +} + +static inline void ssp_port_write(struct ti_ssp *ssp, int port, int reg, + u32 val) +{ + ssp_write(ssp, ssp_port_base[port] + reg, val); +} + +static inline void ssp_port_rmw(struct ti_ssp *ssp, int port, int reg, + u32 mask, u32 bits) +{ + ssp_rmw(ssp, ssp_port_base[port] + reg, mask, bits); +} + +static inline void ssp_port_clr_bits(struct ti_ssp *ssp, int port, int reg, + u32 bits) +{ + ssp_port_rmw(ssp, port, reg, bits, 0); +} + +static inline void ssp_port_set_bits(struct ti_ssp *ssp, int port, int reg, + u32 bits) +{ + ssp_port_rmw(ssp, port, reg, 0, bits); +} + +/* Called to setup port clock mode, caller must hold ssp->lock */ +static int __set_mode(struct ti_ssp *ssp, int port, int mode) +{ + mode &= SSP_PORT_CONFIG_MASK; + ssp_port_rmw(ssp, port, PORT_CFG_1, SSP_PORT_CONFIG_MASK, mode); + + return 0; +} + +int ti_ssp_set_mode(struct device *dev, int mode) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev); + int ret; + + spin_lock(&ssp->lock); + ret = __set_mode(ssp, port, mode); + spin_unlock(&ssp->lock); + + return ret; +} +EXPORT_SYMBOL(ti_ssp_set_mode); + +/* Called to setup iosel2, caller must hold ssp->lock */ +static void __set_iosel2(struct ti_ssp *ssp, u32 mask, u32 val) +{ + ssp->iosel2 = (ssp->iosel2 & ~mask) | val; + ssp_write(ssp, REG_IOSEL_2, ssp->iosel2); +} + +/* Called to setup port iosel, caller must hold ssp->lock */ +static void __set_iosel(struct ti_ssp *ssp, int port, u32 iosel) +{ + unsigned val, shift = port ? 16 : 0; + + /* IOSEL1 gets the least significant 16 bits */ + val = ssp_read(ssp, REG_IOSEL_1); + val &= 0xffff << (port ? 0 : 16); + val |= (iosel & 0xffff) << (port ? 16 : 0); + ssp_write(ssp, REG_IOSEL_1, val); + + /* IOSEL2 gets the most significant 16 bits */ + val = (iosel >> 16) & 0x7; + __set_iosel2(ssp, 0x7 << shift, val << shift); +} + +int ti_ssp_set_iosel(struct device *dev, u32 iosel) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev); + + spin_lock(&ssp->lock); + __set_iosel(ssp, port, iosel); + spin_unlock(&ssp->lock); + + return 0; +} +EXPORT_SYMBOL(ti_ssp_set_iosel); + +int ti_ssp_load(struct device *dev, int offs, u32* prog, int len) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev); + int i; + + if (len > SSP_PORT_SEQRAM_SIZE) + return -ENOSPC; + + spin_lock(&ssp->lock); + + /* Enable SeqRAM access */ + ssp_port_set_bits(ssp, port, PORT_CFG_2, SSP_SEQRAM_WR_EN); + + /* Copy code */ + for (i = 0; i < len; i++) { + __raw_writel(prog[i], ssp->regs + offs + 4*i + + ssp_port_seqram[port]); + } + + /* Disable SeqRAM access */ + ssp_port_clr_bits(ssp, port, PORT_CFG_2, SSP_SEQRAM_WR_EN); + + spin_unlock(&ssp->lock); + + return 0; +} +EXPORT_SYMBOL(ti_ssp_load); + +int ti_ssp_raw_read(struct device *dev) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev); + int shift = port ? 27 : 11; + + return (ssp_read(ssp, REG_IOSEL_2) >> shift) & 0xf; +} +EXPORT_SYMBOL(ti_ssp_raw_read); + +int ti_ssp_raw_write(struct device *dev, u32 val) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev), shift; + + spin_lock(&ssp->lock); + + shift = port ? 22 : 6; + val &= 0xf; + __set_iosel2(ssp, 0xf << shift, val << shift); + + spin_unlock(&ssp->lock); + + return 0; +} +EXPORT_SYMBOL(ti_ssp_raw_write); + +static inline int __xfer_done(struct ti_ssp *ssp, int port) +{ + return !(ssp_port_read(ssp, port, PORT_CFG_1) & SSP_BUSY); +} + +int ti_ssp_run(struct device *dev, u32 pc, u32 input, u32 *output) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev); + int ret; + + if (pc & ~(0x3f)) + return -EINVAL; + + /* Grab ssp->lock to serialize rmw on ssp registers */ + spin_lock(&ssp->lock); + + ssp_port_write(ssp, port, PORT_ADDR, input >> 16); + ssp_port_write(ssp, port, PORT_DATA, input & 0xffff); + ssp_port_rmw(ssp, port, PORT_CFG_1, 0x3f, pc); + + /* grab wait queue head lock to avoid race with the isr */ + spin_lock_irq(&ssp->wqh.lock); + + /* kick off sequence execution in hardware */ + ssp_port_set_bits(ssp, port, PORT_CFG_1, SSP_START); + + /* drop ssp lock; no register writes beyond this */ + spin_unlock(&ssp->lock); + + ret = wait_event_interruptible_locked_irq(ssp->wqh, + __xfer_done(ssp, port)); + spin_unlock_irq(&ssp->wqh.lock); + + if (ret < 0) + return ret; + + if (output) { + *output = (ssp_port_read(ssp, port, PORT_ADDR) << 16) | + (ssp_port_read(ssp, port, PORT_DATA) & 0xffff); + } + + ret = ssp_port_read(ssp, port, PORT_STATE) & 0x3f; /* stop address */ + + return ret; +} +EXPORT_SYMBOL(ti_ssp_run); + +static irqreturn_t ti_ssp_interrupt(int irq, void *dev_data) +{ + struct ti_ssp *ssp = dev_data; + + spin_lock(&ssp->wqh.lock); + + ssp_write(ssp, REG_INTR_ST, 0x3); + wake_up_locked(&ssp->wqh); + + spin_unlock(&ssp->wqh.lock); + + return IRQ_HANDLED; +} + +static int __devinit ti_ssp_probe(struct platform_device *pdev) +{ + static struct ti_ssp *ssp; + const struct ti_ssp_data *pdata = pdev->dev.platform_data; + int error = 0, prediv = 0xff, id; + unsigned long sysclk; + struct device *dev = &pdev->dev; + struct mfd_cell cells[2]; + + ssp = kzalloc(sizeof(*ssp), GFP_KERNEL); + if (!ssp) { + dev_err(dev, "cannot allocate device info\n"); + return -ENOMEM; + } + + ssp->dev = dev; + dev_set_drvdata(dev, ssp); + + ssp->res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!ssp->res) { + error = -ENODEV; + dev_err(dev, "cannot determine register area\n"); + goto error_res; + } + + if (!request_mem_region(ssp->res->start, resource_size(ssp->res), + pdev->name)) { + error = -ENOMEM; + dev_err(dev, "cannot claim register memory\n"); + goto error_res; + } + + ssp->regs = ioremap(ssp->res->start, resource_size(ssp->res)); + if (!ssp->regs) { + error = -ENOMEM; + dev_err(dev, "cannot map register memory\n"); + goto error_map; + } + + ssp->clk = clk_get(dev, NULL); + if (IS_ERR(ssp->clk)) { + error = PTR_ERR(ssp->clk); + dev_err(dev, "cannot claim device clock\n"); + goto error_clk; + } + + ssp->irq = platform_get_irq(pdev, 0); + if (ssp->irq < 0) { + error = -ENODEV; + dev_err(dev, "unknown irq\n"); + goto error_irq; + } + + error = request_threaded_irq(ssp->irq, NULL, ti_ssp_interrupt, 0, + dev_name(dev), ssp); + if (error < 0) { + dev_err(dev, "cannot acquire irq\n"); + goto error_irq; + } + + spin_lock_init(&ssp->lock); + init_waitqueue_head(&ssp->wqh); + + /* Power on and initialize SSP */ + error = clk_enable(ssp->clk); + if (error) { + dev_err(dev, "cannot enable device clock\n"); + goto error_enable; + } + + /* Reset registers to a sensible known state */ + ssp_write(ssp, REG_IOSEL_1, 0); + ssp_write(ssp, REG_IOSEL_2, 0); + ssp_write(ssp, REG_INTR_EN, 0x3); + ssp_write(ssp, REG_INTR_ST, 0x3); + ssp_write(ssp, REG_TEST_CTRL, 0); + ssp_port_write(ssp, 0, PORT_CFG_1, SSP_PORT_ASL); + ssp_port_write(ssp, 1, PORT_CFG_1, SSP_PORT_ASL); + ssp_port_write(ssp, 0, PORT_CFG_2, SSP_PORT_CFO1); + ssp_port_write(ssp, 1, PORT_CFG_2, SSP_PORT_CFO1); + + sysclk = clk_get_rate(ssp->clk); + if (pdata && pdata->out_clock) + prediv = (sysclk / pdata->out_clock) - 1; + prediv = clamp(prediv, 0, 0xff); + ssp_rmw(ssp, REG_PREDIV, 0xff, prediv); + + memset(cells, 0, sizeof(cells)); + for (id = 0; id < 2; id++) { + const struct ti_ssp_dev_data *data = &pdata->dev_data[id]; + + cells[id].id = id; + cells[id].name = data->dev_name; + cells[id].platform_data = data->pdata; + cells[id].data_size = data->pdata_size; + } + + error = mfd_add_devices(dev, 0, cells, 2, NULL, 0); + if (error < 0) { + dev_err(dev, "cannot add mfd cells\n"); + goto error_enable; + } + + return 0; + +error_enable: + free_irq(ssp->irq, ssp); +error_irq: + clk_put(ssp->clk); +error_clk: + iounmap(ssp->regs); +error_map: + release_mem_region(ssp->res->start, resource_size(ssp->res)); +error_res: + kfree(ssp); + return error; +} + +static int __devexit ti_ssp_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct ti_ssp *ssp = dev_get_drvdata(dev); + + mfd_remove_devices(dev); + clk_disable(ssp->clk); + free_irq(ssp->irq, ssp); + clk_put(ssp->clk); + iounmap(ssp->regs); + release_mem_region(ssp->res->start, resource_size(ssp->res)); + kfree(ssp); + dev_set_drvdata(dev, NULL); + return 0; +} + +static struct platform_driver ti_ssp_driver = { + .probe = ti_ssp_probe, + .remove = __devexit_p(ti_ssp_remove), + .driver = { + .name = "ti-ssp", + .owner = THIS_MODULE, + } +}; + +static int __init ti_ssp_init(void) +{ + return platform_driver_register(&ti_ssp_driver); +} +module_init(ti_ssp_init); + +static void __exit ti_ssp_exit(void) +{ + platform_driver_unregister(&ti_ssp_driver); +} +module_exit(ti_ssp_exit); + +MODULE_DESCRIPTION("Sequencer Serial Port (SSP) Driver"); +MODULE_AUTHOR("Cyril Chemparathy"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ti-ssp"); |