tifm_7xx1.c - This C code implements a driver for TI FlashM…

/drivers/misc/tifm_7xx1.c

http://github.com/mirrors/linux · C · 441 lines · 350 code · 81 blank · 10 comment · 56 complexity · 174a01cbd90d565e1914fbcaca2be3ba MD5 · raw file


// SPDX-License-Identifier: GPL-2.0-only
/*
 *  tifm_7xx1.c - TI FlashMedia driver
 *
 *  Copyright (C) 2006 Alex Dubov <oakad@yahoo.com>
 */

#include <linux/tifm.h>
#include <linux/dma-mapping.h>
#include <linux/module.h>

#define DRIVER_NAME "tifm_7xx1"
#define DRIVER_VERSION "0.8"

#define TIFM_IRQ_ENABLE           0x80000000
#define TIFM_IRQ_SOCKMASK(x)      (x)
#define TIFM_IRQ_CARDMASK(x)      ((x) << 8)
#define TIFM_IRQ_FIFOMASK(x)      ((x) << 16)
#define TIFM_IRQ_SETALL           0xffffffff

static void tifm_7xx1_dummy_eject(struct tifm_adapter *fm,
				  struct tifm_dev *sock)
{
}

static void tifm_7xx1_eject(struct tifm_adapter *fm, struct tifm_dev *sock)
{
	unsigned long flags;

	spin_lock_irqsave(&fm->lock, flags);
	fm->socket_change_set |= 1 << sock->socket_id;
	tifm_queue_work(&fm->media_switcher);
	spin_unlock_irqrestore(&fm->lock, flags);
}

static irqreturn_t tifm_7xx1_isr(int irq, void *dev_id)
{
	struct tifm_adapter *fm = dev_id;
	struct tifm_dev *sock;
	unsigned int irq_status, cnt;

	spin_lock(&fm->lock);
	irq_status = readl(fm->addr + FM_INTERRUPT_STATUS);
	if (irq_status == 0 || irq_status == (~0)) {
		spin_unlock(&fm->lock);
		return IRQ_NONE;
	}

	if (irq_status & TIFM_IRQ_ENABLE) {
		writel(TIFM_IRQ_ENABLE, fm->addr + FM_CLEAR_INTERRUPT_ENABLE);

		for (cnt = 0; cnt < fm->num_sockets; cnt++) {
			sock = fm->sockets[cnt];
			if (sock) {
				if ((irq_status >> cnt) & TIFM_IRQ_FIFOMASK(1))
					sock->data_event(sock);
				if ((irq_status >> cnt) & TIFM_IRQ_CARDMASK(1))
					sock->card_event(sock);
			}
		}

		fm->socket_change_set |= irq_status
					 & ((1 << fm->num_sockets) - 1);
	}
	writel(irq_status, fm->addr + FM_INTERRUPT_STATUS);

	if (fm->finish_me)
		complete_all(fm->finish_me);
	else if (!fm->socket_change_set)
		writel(TIFM_IRQ_ENABLE, fm->addr + FM_SET_INTERRUPT_ENABLE);
	else
		tifm_queue_work(&fm->media_switcher);

	spin_unlock(&fm->lock);
	return IRQ_HANDLED;
}

static unsigned char tifm_7xx1_toggle_sock_power(char __iomem *sock_addr)
{
	unsigned int s_state;
	int cnt;

	writel(0x0e00, sock_addr + SOCK_CONTROL);

	for (cnt = 16; cnt <= 256; cnt <<= 1) {
		if (!(TIFM_SOCK_STATE_POWERED
		      & readl(sock_addr + SOCK_PRESENT_STATE)))
			break;

		msleep(cnt);
	}

	s_state = readl(sock_addr + SOCK_PRESENT_STATE);
	if (!(TIFM_SOCK_STATE_OCCUPIED & s_state))
		return 0;

	writel(readl(sock_addr + SOCK_CONTROL) | TIFM_CTRL_LED,
	       sock_addr + SOCK_CONTROL);

	/* xd needs some extra time before power on */
	if (((readl(sock_addr + SOCK_PRESENT_STATE) >> 4) & 7)
	    == TIFM_TYPE_XD)
		msleep(40);

	writel((s_state & TIFM_CTRL_POWER_MASK) | 0x0c00,
	       sock_addr + SOCK_CONTROL);
	/* wait for power to stabilize */
	msleep(20);
	for (cnt = 16; cnt <= 256; cnt <<= 1) {
		if ((TIFM_SOCK_STATE_POWERED
		     & readl(sock_addr + SOCK_PRESENT_STATE)))
			break;

		msleep(cnt);
	}

	writel(readl(sock_addr + SOCK_CONTROL) & (~TIFM_CTRL_LED),
	       sock_addr + SOCK_CONTROL);

	return (readl(sock_addr + SOCK_PRESENT_STATE) >> 4) & 7;
}

inline static void tifm_7xx1_sock_power_off(char __iomem *sock_addr)
{
	writel((~TIFM_CTRL_POWER_MASK) & readl(sock_addr + SOCK_CONTROL),
	       sock_addr + SOCK_CONTROL);
}

inline static char __iomem *
tifm_7xx1_sock_addr(char __iomem *base_addr, unsigned int sock_num)
{
	return base_addr + ((sock_num + 1) << 10);
}

static void tifm_7xx1_switch_media(struct work_struct *work)
{
	struct tifm_adapter *fm = container_of(work, struct tifm_adapter,
					       media_switcher);
	struct tifm_dev *sock;
	char __iomem *sock_addr;
	unsigned long flags;
	unsigned char media_id;
	unsigned int socket_change_set, cnt;

	spin_lock_irqsave(&fm->lock, flags);
	socket_change_set = fm->socket_change_set;
	fm->socket_change_set = 0;

	dev_dbg(fm->dev.parent, "checking media set %x\n",
		socket_change_set);

	if (!socket_change_set) {
		spin_unlock_irqrestore(&fm->lock, flags);
		return;
	}

	for (cnt = 0; cnt < fm->num_sockets; cnt++) {
		if (!(socket_change_set & (1 << cnt)))
			continue;
		sock = fm->sockets[cnt];
		if (sock) {
			printk(KERN_INFO
			       "%s : demand removing card from socket %u:%u\n",
			       dev_name(&fm->dev), fm->id, cnt);
			fm->sockets[cnt] = NULL;
			sock_addr = sock->addr;
			spin_unlock_irqrestore(&fm->lock, flags);
			device_unregister(&sock->dev);
			spin_lock_irqsave(&fm->lock, flags);
			tifm_7xx1_sock_power_off(sock_addr);
			writel(0x0e00, sock_addr + SOCK_CONTROL);
		}

		spin_unlock_irqrestore(&fm->lock, flags);

		media_id = tifm_7xx1_toggle_sock_power(
				tifm_7xx1_sock_addr(fm->addr, cnt));

		// tifm_alloc_device will check if media_id is valid
		sock = tifm_alloc_device(fm, cnt, media_id);
		if (sock) {
			sock->addr = tifm_7xx1_sock_addr(fm->addr, cnt);

			if (!device_register(&sock->dev)) {
				spin_lock_irqsave(&fm->lock, flags);
				if (!fm->sockets[cnt]) {
					fm->sockets[cnt] = sock;
					sock = NULL;
				}
				spin_unlock_irqrestore(&fm->lock, flags);
			}
			if (sock)
				tifm_free_device(&sock->dev);
		}
		spin_lock_irqsave(&fm->lock, flags);
	}

	writel(TIFM_IRQ_FIFOMASK(socket_change_set)
	       | TIFM_IRQ_CARDMASK(socket_change_set),
	       fm->addr + FM_CLEAR_INTERRUPT_ENABLE);

	writel(TIFM_IRQ_FIFOMASK(socket_change_set)
	       | TIFM_IRQ_CARDMASK(socket_change_set),
	       fm->addr + FM_SET_INTERRUPT_ENABLE);

	writel(TIFM_IRQ_ENABLE, fm->addr + FM_SET_INTERRUPT_ENABLE);
	spin_unlock_irqrestore(&fm->lock, flags);
}

#ifdef CONFIG_PM

static int tifm_7xx1_suspend(struct pci_dev *dev, pm_message_t state)
{
	struct tifm_adapter *fm = pci_get_drvdata(dev);
	int cnt;

	dev_dbg(&dev->dev, "suspending host\n");

	for (cnt = 0; cnt < fm->num_sockets; cnt++) {
		if (fm->sockets[cnt])
			tifm_7xx1_sock_power_off(fm->sockets[cnt]->addr);
	}

	pci_save_state(dev);
	pci_enable_wake(dev, pci_choose_state(dev, state), 0);
	pci_disable_device(dev);
	pci_set_power_state(dev, pci_choose_state(dev, state));
	return 0;
}

static int tifm_7xx1_resume(struct pci_dev *dev)
{
	struct tifm_adapter *fm = pci_get_drvdata(dev);
	int rc;
	unsigned long timeout;
	unsigned int good_sockets = 0, bad_sockets = 0;
	unsigned long flags;
	/* Maximum number of entries is 4 */
	unsigned char new_ids[4];
	DECLARE_COMPLETION_ONSTACK(finish_resume);

	if (WARN_ON(fm->num_sockets > ARRAY_SIZE(new_ids)))
		return -ENXIO;

	pci_set_power_state(dev, PCI_D0);
	pci_restore_state(dev);
	rc = pci_enable_device(dev);
	if (rc)
		return rc;
	pci_set_master(dev);

	dev_dbg(&dev->dev, "resuming host\n");

	for (rc = 0; rc < fm->num_sockets; rc++)
		new_ids[rc] = tifm_7xx1_toggle_sock_power(
					tifm_7xx1_sock_addr(fm->addr, rc));
	spin_lock_irqsave(&fm->lock, flags);
	for (rc = 0; rc < fm->num_sockets; rc++) {
		if (fm->sockets[rc]) {
			if (fm->sockets[rc]->type == new_ids[rc])
				good_sockets |= 1 << rc;
			else
				bad_sockets |= 1 << rc;
		}
	}

	writel(TIFM_IRQ_ENABLE | TIFM_IRQ_SOCKMASK((1 << fm->num_sockets) - 1),
	       fm->addr + FM_SET_INTERRUPT_ENABLE);
	dev_dbg(&dev->dev, "change sets on resume: good %x, bad %x\n",
		good_sockets, bad_sockets);

	fm->socket_change_set = 0;
	if (good_sockets) {
		fm->finish_me = &finish_resume;
		spin_unlock_irqrestore(&fm->lock, flags);
		timeout = wait_for_completion_timeout(&finish_resume, HZ);
		dev_dbg(&dev->dev, "wait returned %lu\n", timeout);
		writel(TIFM_IRQ_FIFOMASK(good_sockets)
		       | TIFM_IRQ_CARDMASK(good_sockets),
		       fm->addr + FM_CLEAR_INTERRUPT_ENABLE);
		writel(TIFM_IRQ_FIFOMASK(good_sockets)
		       | TIFM_IRQ_CARDMASK(good_sockets),
		       fm->addr + FM_SET_INTERRUPT_ENABLE);
		spin_lock_irqsave(&fm->lock, flags);
		fm->finish_me = NULL;
		fm->socket_change_set ^= good_sockets & fm->socket_change_set;
	}

	fm->socket_change_set |= bad_sockets;
	if (fm->socket_change_set)
		tifm_queue_work(&fm->media_switcher);

	spin_unlock_irqrestore(&fm->lock, flags);
	writel(TIFM_IRQ_ENABLE,
	       fm->addr + FM_SET_INTERRUPT_ENABLE);

	return 0;
}

#else

#define tifm_7xx1_suspend NULL
#define tifm_7xx1_resume NULL

#endif /* CONFIG_PM */

static int tifm_7xx1_dummy_has_ms_pif(struct tifm_adapter *fm,
				      struct tifm_dev *sock)
{
	return 0;
}

static int tifm_7xx1_has_ms_pif(struct tifm_adapter *fm, struct tifm_dev *sock)
{
	if (((fm->num_sockets == 4) && (sock->socket_id == 2))
	    || ((fm->num_sockets == 2) && (sock->socket_id == 0)))
		return 1;

	return 0;
}

static int tifm_7xx1_probe(struct pci_dev *dev,
			   const struct pci_device_id *dev_id)
{
	struct tifm_adapter *fm;
	int pci_dev_busy = 0;
	int rc;

	rc = pci_set_dma_mask(dev, DMA_BIT_MASK(32));
	if (rc)
		return rc;

	rc = pci_enable_device(dev);
	if (rc)
		return rc;

	pci_set_master(dev);

	rc = pci_request_regions(dev, DRIVER_NAME);
	if (rc) {
		pci_dev_busy = 1;
		goto err_out;
	}

	pci_intx(dev, 1);

	fm = tifm_alloc_adapter(dev->device == PCI_DEVICE_ID_TI_XX21_XX11_FM
				? 4 : 2, &dev->dev);
	if (!fm) {
		rc = -ENOMEM;
		goto err_out_int;
	}

	INIT_WORK(&fm->media_switcher, tifm_7xx1_switch_media);
	fm->eject = tifm_7xx1_eject;
	fm->has_ms_pif = tifm_7xx1_has_ms_pif;
	pci_set_drvdata(dev, fm);

	fm->addr = pci_ioremap_bar(dev, 0);
	if (!fm->addr) {
		rc = -ENODEV;
		goto err_out_free;
	}

	rc = request_irq(dev->irq, tifm_7xx1_isr, IRQF_SHARED, DRIVER_NAME, fm);
	if (rc)
		goto err_out_unmap;

	rc = tifm_add_adapter(fm);
	if (rc)
		goto err_out_irq;

	writel(TIFM_IRQ_ENABLE | TIFM_IRQ_SOCKMASK((1 << fm->num_sockets) - 1),
	       fm->addr + FM_CLEAR_INTERRUPT_ENABLE);
	writel(TIFM_IRQ_ENABLE | TIFM_IRQ_SOCKMASK((1 << fm->num_sockets) - 1),
	       fm->addr + FM_SET_INTERRUPT_ENABLE);
	return 0;

err_out_irq:
	free_irq(dev->irq, fm);
err_out_unmap:
	iounmap(fm->addr);
err_out_free:
	tifm_free_adapter(fm);
err_out_int:
	pci_intx(dev, 0);
	pci_release_regions(dev);
err_out:
	if (!pci_dev_busy)
		pci_disable_device(dev);
	return rc;
}

static void tifm_7xx1_remove(struct pci_dev *dev)
{
	struct tifm_adapter *fm = pci_get_drvdata(dev);
	int cnt;

	fm->eject = tifm_7xx1_dummy_eject;
	fm->has_ms_pif = tifm_7xx1_dummy_has_ms_pif;
	writel(TIFM_IRQ_SETALL, fm->addr + FM_CLEAR_INTERRUPT_ENABLE);
	free_irq(dev->irq, fm);

	tifm_remove_adapter(fm);

	for (cnt = 0; cnt < fm->num_sockets; cnt++)
		tifm_7xx1_sock_power_off(tifm_7xx1_sock_addr(fm->addr, cnt));

	iounmap(fm->addr);
	pci_intx(dev, 0);
	pci_release_regions(dev);

	pci_disable_device(dev);
	tifm_free_adapter(fm);
}

static const struct pci_device_id tifm_7xx1_pci_tbl[] = {
	{ PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_XX21_XX11_FM, PCI_ANY_ID,
	  PCI_ANY_ID, 0, 0, 0 }, /* xx21 - the one I have */
        { PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_XX12_FM, PCI_ANY_ID,
	  PCI_ANY_ID, 0, 0, 0 },
	{ PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_XX20_FM, PCI_ANY_ID,
	  PCI_ANY_ID, 0, 0, 0 },
	{ }
};

static struct pci_driver tifm_7xx1_driver = {
	.name = DRIVER_NAME,
	.id_table = tifm_7xx1_pci_tbl,
	.probe = tifm_7xx1_probe,
	.remove = tifm_7xx1_remove,
	.suspend = tifm_7xx1_suspend,
	.resume = tifm_7xx1_resume,
};

module_pci_driver(tifm_7xx1_driver);
MODULE_AUTHOR("Alex Dubov");
MODULE_DESCRIPTION("TI FlashMedia host driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, tifm_7xx1_pci_tbl);
MODULE_VERSION(DRIVER_VERSION);

Summary ✨

This C code implements a driver for TI FlashMedia devices, which are used to interface with flash memory chips on embedded systems. The driver provides functionality for managing the device’s interrupt handling, power management, and communication with the host system. It also includes support for ejecting the device and handling media switching.

Alerts (2)

Complexity hotspot; lines 315 to 316 (total complexity: 8)
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