staging: rtl8192u: Remove NULL check before kfree
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / ata / pata_samsung_cf.c
blob8a51d673e5b29e5073978ba9cdc11baa314fc88f
1 /*
2 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
3 * http://www.samsung.com
5 * PATA driver for Samsung SoCs.
6 * Supports CF Interface in True IDE mode. Currently only PIO mode has been
7 * implemented; UDMA support has to be added.
9 * Based on:
10 * PATA driver for AT91SAM9260 Static Memory Controller
11 * PATA driver for Toshiba SCC controller
13 * This program is free software; you can redistribute it and/or modify it
14 * under the terms of the GNU General Public License version 2
15 * as published by the Free Software Foundation.
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/clk.h>
22 #include <linux/libata.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
26 #include <plat/ata.h>
27 #include <plat/regs-ata.h>
29 #define DRV_NAME "pata_samsung_cf"
30 #define DRV_VERSION "0.1"
32 enum s3c_cpu_type {
33 TYPE_S3C64XX,
34 TYPE_S5PC100,
35 TYPE_S5PV210,
39 * struct s3c_ide_info - S3C PATA instance.
40 * @clk: The clock resource for this controller.
41 * @ide_addr: The area mapped for the hardware registers.
42 * @sfr_addr: The area mapped for the special function registers.
43 * @irq: The IRQ number we are using.
44 * @cpu_type: The exact type of this controller.
45 * @fifo_status_reg: The ATA_FIFO_STATUS register offset.
47 struct s3c_ide_info {
48 struct clk *clk;
49 void __iomem *ide_addr;
50 void __iomem *sfr_addr;
51 unsigned int irq;
52 enum s3c_cpu_type cpu_type;
53 unsigned int fifo_status_reg;
56 static void pata_s3c_set_endian(void __iomem *s3c_ide_regbase, u8 mode)
58 u32 reg = readl(s3c_ide_regbase + S3C_ATA_CFG);
59 reg = mode ? (reg & ~S3C_ATA_CFG_SWAP) : (reg | S3C_ATA_CFG_SWAP);
60 writel(reg, s3c_ide_regbase + S3C_ATA_CFG);
63 static void pata_s3c_cfg_mode(void __iomem *s3c_ide_sfrbase)
65 /* Select true-ide as the internal operating mode */
66 writel(readl(s3c_ide_sfrbase + S3C_CFATA_MUX) | S3C_CFATA_MUX_TRUEIDE,
67 s3c_ide_sfrbase + S3C_CFATA_MUX);
70 static unsigned long
71 pata_s3c_setup_timing(struct s3c_ide_info *info, const struct ata_timing *ata)
73 int t1 = ata->setup;
74 int t2 = ata->act8b;
75 int t2i = ata->rec8b;
76 ulong piotime;
78 piotime = ((t2i & 0xff) << 12) | ((t2 & 0xff) << 4) | (t1 & 0xf);
80 return piotime;
83 static void pata_s3c_set_piomode(struct ata_port *ap, struct ata_device *adev)
85 struct s3c_ide_info *info = ap->host->private_data;
86 struct ata_timing timing;
87 int cycle_time;
88 ulong ata_cfg = readl(info->ide_addr + S3C_ATA_CFG);
89 ulong piotime;
91 /* Enables IORDY if mode requires it */
92 if (ata_pio_need_iordy(adev))
93 ata_cfg |= S3C_ATA_CFG_IORDYEN;
94 else
95 ata_cfg &= ~S3C_ATA_CFG_IORDYEN;
97 cycle_time = (int)(1000000000UL / clk_get_rate(info->clk));
99 ata_timing_compute(adev, adev->pio_mode, &timing,
100 cycle_time * 1000, 0);
102 piotime = pata_s3c_setup_timing(info, &timing);
104 writel(ata_cfg, info->ide_addr + S3C_ATA_CFG);
105 writel(piotime, info->ide_addr + S3C_ATA_PIO_TIME);
109 * Waits until the IDE controller is able to perform next read/write
110 * operation to the disk. Needed for 64XX series boards only.
112 static int wait_for_host_ready(struct s3c_ide_info *info)
114 ulong timeout;
115 void __iomem *fifo_reg = info->ide_addr + info->fifo_status_reg;
117 /* wait for maximum of 20 msec */
118 timeout = jiffies + msecs_to_jiffies(20);
119 while (time_before(jiffies, timeout)) {
120 if ((readl(fifo_reg) >> 28) == 0)
121 return 0;
123 return -EBUSY;
127 * Writes to one of the task file registers.
129 static void ata_outb(struct ata_host *host, u8 addr, void __iomem *reg)
131 struct s3c_ide_info *info = host->private_data;
133 wait_for_host_ready(info);
134 writeb(addr, reg);
138 * Reads from one of the task file registers.
140 static u8 ata_inb(struct ata_host *host, void __iomem *reg)
142 struct s3c_ide_info *info = host->private_data;
143 u8 temp;
145 wait_for_host_ready(info);
146 (void) readb(reg);
147 wait_for_host_ready(info);
148 temp = readb(info->ide_addr + S3C_ATA_PIO_RDATA);
149 return temp;
153 * pata_s3c_tf_load - send taskfile registers to host controller
155 static void pata_s3c_tf_load(struct ata_port *ap,
156 const struct ata_taskfile *tf)
158 struct ata_ioports *ioaddr = &ap->ioaddr;
159 unsigned int is_addr = tf->flags & ATA_TFLAG_ISADDR;
161 if (tf->ctl != ap->last_ctl) {
162 ata_outb(ap->host, tf->ctl, ioaddr->ctl_addr);
163 ap->last_ctl = tf->ctl;
164 ata_wait_idle(ap);
167 if (is_addr && (tf->flags & ATA_TFLAG_LBA48)) {
168 ata_outb(ap->host, tf->hob_feature, ioaddr->feature_addr);
169 ata_outb(ap->host, tf->hob_nsect, ioaddr->nsect_addr);
170 ata_outb(ap->host, tf->hob_lbal, ioaddr->lbal_addr);
171 ata_outb(ap->host, tf->hob_lbam, ioaddr->lbam_addr);
172 ata_outb(ap->host, tf->hob_lbah, ioaddr->lbah_addr);
175 if (is_addr) {
176 ata_outb(ap->host, tf->feature, ioaddr->feature_addr);
177 ata_outb(ap->host, tf->nsect, ioaddr->nsect_addr);
178 ata_outb(ap->host, tf->lbal, ioaddr->lbal_addr);
179 ata_outb(ap->host, tf->lbam, ioaddr->lbam_addr);
180 ata_outb(ap->host, tf->lbah, ioaddr->lbah_addr);
183 if (tf->flags & ATA_TFLAG_DEVICE)
184 ata_outb(ap->host, tf->device, ioaddr->device_addr);
186 ata_wait_idle(ap);
190 * pata_s3c_tf_read - input device's ATA taskfile shadow registers
192 static void pata_s3c_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
194 struct ata_ioports *ioaddr = &ap->ioaddr;
196 tf->feature = ata_inb(ap->host, ioaddr->error_addr);
197 tf->nsect = ata_inb(ap->host, ioaddr->nsect_addr);
198 tf->lbal = ata_inb(ap->host, ioaddr->lbal_addr);
199 tf->lbam = ata_inb(ap->host, ioaddr->lbam_addr);
200 tf->lbah = ata_inb(ap->host, ioaddr->lbah_addr);
201 tf->device = ata_inb(ap->host, ioaddr->device_addr);
203 if (tf->flags & ATA_TFLAG_LBA48) {
204 ata_outb(ap->host, tf->ctl | ATA_HOB, ioaddr->ctl_addr);
205 tf->hob_feature = ata_inb(ap->host, ioaddr->error_addr);
206 tf->hob_nsect = ata_inb(ap->host, ioaddr->nsect_addr);
207 tf->hob_lbal = ata_inb(ap->host, ioaddr->lbal_addr);
208 tf->hob_lbam = ata_inb(ap->host, ioaddr->lbam_addr);
209 tf->hob_lbah = ata_inb(ap->host, ioaddr->lbah_addr);
210 ata_outb(ap->host, tf->ctl, ioaddr->ctl_addr);
211 ap->last_ctl = tf->ctl;
216 * pata_s3c_exec_command - issue ATA command to host controller
218 static void pata_s3c_exec_command(struct ata_port *ap,
219 const struct ata_taskfile *tf)
221 ata_outb(ap->host, tf->command, ap->ioaddr.command_addr);
222 ata_sff_pause(ap);
226 * pata_s3c_check_status - Read device status register
228 static u8 pata_s3c_check_status(struct ata_port *ap)
230 return ata_inb(ap->host, ap->ioaddr.status_addr);
234 * pata_s3c_check_altstatus - Read alternate device status register
236 static u8 pata_s3c_check_altstatus(struct ata_port *ap)
238 return ata_inb(ap->host, ap->ioaddr.altstatus_addr);
242 * pata_s3c_data_xfer - Transfer data by PIO
244 unsigned int pata_s3c_data_xfer(struct ata_device *dev, unsigned char *buf,
245 unsigned int buflen, int rw)
247 struct ata_port *ap = dev->link->ap;
248 struct s3c_ide_info *info = ap->host->private_data;
249 void __iomem *data_addr = ap->ioaddr.data_addr;
250 unsigned int words = buflen >> 1, i;
251 u16 *data_ptr = (u16 *)buf;
253 /* Requires wait same as in ata_inb/ata_outb */
254 if (rw == READ)
255 for (i = 0; i < words; i++, data_ptr++) {
256 wait_for_host_ready(info);
257 (void) readw(data_addr);
258 wait_for_host_ready(info);
259 *data_ptr = readw(info->ide_addr
260 + S3C_ATA_PIO_RDATA);
262 else
263 for (i = 0; i < words; i++, data_ptr++) {
264 wait_for_host_ready(info);
265 writew(*data_ptr, data_addr);
268 if (buflen & 0x01)
269 dev_err(ap->dev, "unexpected trailing data\n");
271 return words << 1;
275 * pata_s3c_dev_select - Select device on ATA bus
277 static void pata_s3c_dev_select(struct ata_port *ap, unsigned int device)
279 u8 tmp = ATA_DEVICE_OBS;
281 if (device != 0)
282 tmp |= ATA_DEV1;
284 ata_outb(ap->host, tmp, ap->ioaddr.device_addr);
285 ata_sff_pause(ap);
289 * pata_s3c_devchk - PATA device presence detection
291 static unsigned int pata_s3c_devchk(struct ata_port *ap,
292 unsigned int device)
294 struct ata_ioports *ioaddr = &ap->ioaddr;
295 u8 nsect, lbal;
297 pata_s3c_dev_select(ap, device);
299 ata_outb(ap->host, 0x55, ioaddr->nsect_addr);
300 ata_outb(ap->host, 0xaa, ioaddr->lbal_addr);
302 ata_outb(ap->host, 0xaa, ioaddr->nsect_addr);
303 ata_outb(ap->host, 0x55, ioaddr->lbal_addr);
305 ata_outb(ap->host, 0x55, ioaddr->nsect_addr);
306 ata_outb(ap->host, 0xaa, ioaddr->lbal_addr);
308 nsect = ata_inb(ap->host, ioaddr->nsect_addr);
309 lbal = ata_inb(ap->host, ioaddr->lbal_addr);
311 if ((nsect == 0x55) && (lbal == 0xaa))
312 return 1; /* we found a device */
314 return 0; /* nothing found */
318 * pata_s3c_wait_after_reset - wait for devices to become ready after reset
320 static int pata_s3c_wait_after_reset(struct ata_link *link,
321 unsigned long deadline)
323 int rc;
325 ata_msleep(link->ap, ATA_WAIT_AFTER_RESET);
327 /* always check readiness of the master device */
328 rc = ata_sff_wait_ready(link, deadline);
329 /* -ENODEV means the odd clown forgot the D7 pulldown resistor
330 * and TF status is 0xff, bail out on it too.
332 if (rc)
333 return rc;
335 return 0;
339 * pata_s3c_bus_softreset - PATA device software reset
341 static unsigned int pata_s3c_bus_softreset(struct ata_port *ap,
342 unsigned long deadline)
344 struct ata_ioports *ioaddr = &ap->ioaddr;
346 /* software reset. causes dev0 to be selected */
347 ata_outb(ap->host, ap->ctl, ioaddr->ctl_addr);
348 udelay(20);
349 ata_outb(ap->host, ap->ctl | ATA_SRST, ioaddr->ctl_addr);
350 udelay(20);
351 ata_outb(ap->host, ap->ctl, ioaddr->ctl_addr);
352 ap->last_ctl = ap->ctl;
354 return pata_s3c_wait_after_reset(&ap->link, deadline);
358 * pata_s3c_softreset - reset host port via ATA SRST
360 static int pata_s3c_softreset(struct ata_link *link, unsigned int *classes,
361 unsigned long deadline)
363 struct ata_port *ap = link->ap;
364 unsigned int devmask = 0;
365 int rc;
366 u8 err;
368 /* determine if device 0 is present */
369 if (pata_s3c_devchk(ap, 0))
370 devmask |= (1 << 0);
372 /* select device 0 again */
373 pata_s3c_dev_select(ap, 0);
375 /* issue bus reset */
376 rc = pata_s3c_bus_softreset(ap, deadline);
377 /* if link is occupied, -ENODEV too is an error */
378 if (rc && rc != -ENODEV) {
379 ata_link_printk(link, KERN_ERR, "SRST failed (errno=%d)\n", rc);
380 return rc;
383 /* determine by signature whether we have ATA or ATAPI devices */
384 classes[0] = ata_sff_dev_classify(&ap->link.device[0],
385 devmask & (1 << 0), &err);
387 return 0;
391 * pata_s3c_set_devctl - Write device control register
393 static void pata_s3c_set_devctl(struct ata_port *ap, u8 ctl)
395 ata_outb(ap->host, ctl, ap->ioaddr.ctl_addr);
398 static struct scsi_host_template pata_s3c_sht = {
399 ATA_PIO_SHT(DRV_NAME),
402 static struct ata_port_operations pata_s3c_port_ops = {
403 .inherits = &ata_sff_port_ops,
404 .sff_check_status = pata_s3c_check_status,
405 .sff_check_altstatus = pata_s3c_check_altstatus,
406 .sff_tf_load = pata_s3c_tf_load,
407 .sff_tf_read = pata_s3c_tf_read,
408 .sff_data_xfer = pata_s3c_data_xfer,
409 .sff_exec_command = pata_s3c_exec_command,
410 .sff_dev_select = pata_s3c_dev_select,
411 .sff_set_devctl = pata_s3c_set_devctl,
412 .softreset = pata_s3c_softreset,
413 .set_piomode = pata_s3c_set_piomode,
416 static struct ata_port_operations pata_s5p_port_ops = {
417 .inherits = &ata_sff_port_ops,
418 .set_piomode = pata_s3c_set_piomode,
421 static void pata_s3c_enable(void *s3c_ide_regbase, bool state)
423 u32 temp = readl(s3c_ide_regbase + S3C_ATA_CTRL);
424 temp = state ? (temp | 1) : (temp & ~1);
425 writel(temp, s3c_ide_regbase + S3C_ATA_CTRL);
428 static irqreturn_t pata_s3c_irq(int irq, void *dev_instance)
430 struct ata_host *host = dev_instance;
431 struct s3c_ide_info *info = host->private_data;
432 u32 reg;
434 reg = readl(info->ide_addr + S3C_ATA_IRQ);
435 writel(reg, info->ide_addr + S3C_ATA_IRQ);
437 return ata_sff_interrupt(irq, dev_instance);
440 static void pata_s3c_hwinit(struct s3c_ide_info *info,
441 struct s3c_ide_platdata *pdata)
443 switch (info->cpu_type) {
444 case TYPE_S3C64XX:
445 /* Configure as big endian */
446 pata_s3c_cfg_mode(info->sfr_addr);
447 pata_s3c_set_endian(info->ide_addr, 1);
448 pata_s3c_enable(info->ide_addr, true);
449 msleep(100);
451 /* Remove IRQ Status */
452 writel(0x1f, info->ide_addr + S3C_ATA_IRQ);
453 writel(0x1b, info->ide_addr + S3C_ATA_IRQ_MSK);
454 break;
456 case TYPE_S5PC100:
457 pata_s3c_cfg_mode(info->sfr_addr);
458 /* FALLTHROUGH */
460 case TYPE_S5PV210:
461 /* Configure as little endian */
462 pata_s3c_set_endian(info->ide_addr, 0);
463 pata_s3c_enable(info->ide_addr, true);
464 msleep(100);
466 /* Remove IRQ Status */
467 writel(0x3f, info->ide_addr + S3C_ATA_IRQ);
468 writel(0x3f, info->ide_addr + S3C_ATA_IRQ_MSK);
469 break;
471 default:
472 BUG();
476 static int __init pata_s3c_probe(struct platform_device *pdev)
478 struct s3c_ide_platdata *pdata = pdev->dev.platform_data;
479 struct device *dev = &pdev->dev;
480 struct s3c_ide_info *info;
481 struct resource *res;
482 struct ata_port *ap;
483 struct ata_host *host;
484 enum s3c_cpu_type cpu_type;
485 int ret;
487 cpu_type = platform_get_device_id(pdev)->driver_data;
489 info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
490 if (!info) {
491 dev_err(dev, "failed to allocate memory for device data\n");
492 return -ENOMEM;
495 info->irq = platform_get_irq(pdev, 0);
497 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
498 if (res == NULL) {
499 dev_err(dev, "failed to get mem resource\n");
500 return -EINVAL;
503 if (!devm_request_mem_region(dev, res->start,
504 resource_size(res), DRV_NAME)) {
505 dev_err(dev, "error requesting register region\n");
506 return -EBUSY;
509 info->ide_addr = devm_ioremap(dev, res->start, resource_size(res));
510 if (!info->ide_addr) {
511 dev_err(dev, "failed to map IO base address\n");
512 return -ENOMEM;
515 info->clk = clk_get(&pdev->dev, "cfcon");
516 if (IS_ERR(info->clk)) {
517 dev_err(dev, "failed to get access to cf controller clock\n");
518 ret = PTR_ERR(info->clk);
519 info->clk = NULL;
520 return ret;
523 clk_enable(info->clk);
525 /* init ata host */
526 host = ata_host_alloc(dev, 1);
527 if (!host) {
528 dev_err(dev, "failed to allocate ide host\n");
529 ret = -ENOMEM;
530 goto stop_clk;
533 ap = host->ports[0];
534 ap->flags |= ATA_FLAG_MMIO;
535 ap->pio_mask = ATA_PIO4;
537 if (cpu_type == TYPE_S3C64XX) {
538 ap->ops = &pata_s3c_port_ops;
539 info->sfr_addr = info->ide_addr + 0x1800;
540 info->ide_addr += 0x1900;
541 info->fifo_status_reg = 0x94;
542 } else if (cpu_type == TYPE_S5PC100) {
543 ap->ops = &pata_s5p_port_ops;
544 info->sfr_addr = info->ide_addr + 0x1800;
545 info->ide_addr += 0x1900;
546 info->fifo_status_reg = 0x84;
547 } else {
548 ap->ops = &pata_s5p_port_ops;
549 info->fifo_status_reg = 0x84;
552 info->cpu_type = cpu_type;
554 if (info->irq <= 0) {
555 ap->flags |= ATA_FLAG_PIO_POLLING;
556 info->irq = 0;
557 ata_port_desc(ap, "no IRQ, using PIO polling\n");
560 ap->ioaddr.cmd_addr = info->ide_addr + S3C_ATA_CMD;
561 ap->ioaddr.data_addr = info->ide_addr + S3C_ATA_PIO_DTR;
562 ap->ioaddr.error_addr = info->ide_addr + S3C_ATA_PIO_FED;
563 ap->ioaddr.feature_addr = info->ide_addr + S3C_ATA_PIO_FED;
564 ap->ioaddr.nsect_addr = info->ide_addr + S3C_ATA_PIO_SCR;
565 ap->ioaddr.lbal_addr = info->ide_addr + S3C_ATA_PIO_LLR;
566 ap->ioaddr.lbam_addr = info->ide_addr + S3C_ATA_PIO_LMR;
567 ap->ioaddr.lbah_addr = info->ide_addr + S3C_ATA_PIO_LHR;
568 ap->ioaddr.device_addr = info->ide_addr + S3C_ATA_PIO_DVR;
569 ap->ioaddr.status_addr = info->ide_addr + S3C_ATA_PIO_CSD;
570 ap->ioaddr.command_addr = info->ide_addr + S3C_ATA_PIO_CSD;
571 ap->ioaddr.altstatus_addr = info->ide_addr + S3C_ATA_PIO_DAD;
572 ap->ioaddr.ctl_addr = info->ide_addr + S3C_ATA_PIO_DAD;
574 ata_port_desc(ap, "mmio cmd 0x%llx ",
575 (unsigned long long)res->start);
577 host->private_data = info;
579 if (pdata && pdata->setup_gpio)
580 pdata->setup_gpio();
582 /* Set endianness and enable the interface */
583 pata_s3c_hwinit(info, pdata);
585 platform_set_drvdata(pdev, host);
587 return ata_host_activate(host, info->irq,
588 info->irq ? pata_s3c_irq : NULL,
589 0, &pata_s3c_sht);
591 stop_clk:
592 clk_disable(info->clk);
593 clk_put(info->clk);
594 return ret;
597 static int __exit pata_s3c_remove(struct platform_device *pdev)
599 struct ata_host *host = platform_get_drvdata(pdev);
600 struct s3c_ide_info *info = host->private_data;
602 ata_host_detach(host);
604 clk_disable(info->clk);
605 clk_put(info->clk);
607 return 0;
610 #ifdef CONFIG_PM
611 static int pata_s3c_suspend(struct device *dev)
613 struct platform_device *pdev = to_platform_device(dev);
614 struct ata_host *host = platform_get_drvdata(pdev);
616 return ata_host_suspend(host, PMSG_SUSPEND);
619 static int pata_s3c_resume(struct device *dev)
621 struct platform_device *pdev = to_platform_device(dev);
622 struct ata_host *host = platform_get_drvdata(pdev);
623 struct s3c_ide_platdata *pdata = pdev->dev.platform_data;
624 struct s3c_ide_info *info = host->private_data;
626 pata_s3c_hwinit(info, pdata);
627 ata_host_resume(host);
629 return 0;
632 static const struct dev_pm_ops pata_s3c_pm_ops = {
633 .suspend = pata_s3c_suspend,
634 .resume = pata_s3c_resume,
636 #endif
638 /* driver device registration */
639 static struct platform_device_id pata_s3c_driver_ids[] = {
641 .name = "s3c64xx-pata",
642 .driver_data = TYPE_S3C64XX,
643 }, {
644 .name = "s5pc100-pata",
645 .driver_data = TYPE_S5PC100,
646 }, {
647 .name = "s5pv210-pata",
648 .driver_data = TYPE_S5PV210,
653 MODULE_DEVICE_TABLE(platform, pata_s3c_driver_ids);
655 static struct platform_driver pata_s3c_driver = {
656 .remove = __exit_p(pata_s3c_remove),
657 .id_table = pata_s3c_driver_ids,
658 .driver = {
659 .name = DRV_NAME,
660 .owner = THIS_MODULE,
661 #ifdef CONFIG_PM
662 .pm = &pata_s3c_pm_ops,
663 #endif
667 static int __init pata_s3c_init(void)
669 return platform_driver_probe(&pata_s3c_driver, pata_s3c_probe);
672 static void __exit pata_s3c_exit(void)
674 platform_driver_unregister(&pata_s3c_driver);
677 module_init(pata_s3c_init);
678 module_exit(pata_s3c_exit);
680 MODULE_AUTHOR("Abhilash Kesavan, <a.kesavan@samsung.com>");
681 MODULE_DESCRIPTION("low-level driver for Samsung PATA controller");
682 MODULE_LICENSE("GPL");
683 MODULE_VERSION(DRV_VERSION);