@@ -30,6 +30,8 @@
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/completion.h>
#include <asm/mach/flash.h>
#include <mach/mxc_nand.h>
@@ -149,7 +151,7 @@ struct mxc_nand_host {
int irq;
int eccsize;
- wait_queue_head_t irq_waitq;
+ struct completion op_completion;
uint8_t *data_buf;
unsigned int buf_start;
@@ -162,6 +164,7 @@ struct mxc_nand_host {
void (*send_read_id)(struct mxc_nand_host *);
uint16_t (*get_dev_status)(struct mxc_nand_host *);
int (*check_int)(struct mxc_nand_host *);
+ void (*irq_control)(struct mxc_nand_host *, int);
};
/* OOB placement block for use with hardware ecc generation */
@@ -214,9 +217,12 @@ static irqreturn_t mxc_nfc_irq(int irq, void *dev_id)
{
struct mxc_nand_host *host = dev_id;
- disable_irq_nosync(irq);
+ if (!host->check_int(host))
+ return IRQ_NONE;
- wake_up(&host->irq_waitq);
+ host->irq_control(host, 0);
+
+ complete(&host->op_completion);
return IRQ_HANDLED;
}
@@ -243,11 +249,54 @@ static int check_int_v1_v2(struct mxc_nand_host *host)
if (!(tmp & NFC_V1_V2_CONFIG2_INT))
return 0;
- writew(tmp & ~NFC_V1_V2_CONFIG2_INT, NFC_V1_V2_CONFIG2);
+ if (!cpu_is_mx21())
+ writew(tmp & ~NFC_V1_V2_CONFIG2_INT, NFC_V1_V2_CONFIG2);
return 1;
}
+/*
+ * It has been observed that the i.MX21 cannot read the CONFIG2:INT bit
+ * if interrupts are masked (CONFIG1:INT_MSK is set). To handle this, the
+ * driver can enable/disable the irq line rather than simply masking the
+ * interrupts.
+ */
+static void irq_control_mx21(struct mxc_nand_host *host, int activate)
+{
+ if (activate)
+ enable_irq(host->irq);
+ else
+ disable_irq_nosync(host->irq);
+}
+
+static void irq_control_v1_v2(struct mxc_nand_host *host, int activate)
+{
+ uint16_t tmp;
+
+ tmp = readw(NFC_V1_V2_CONFIG1);
+
+ if (activate)
+ tmp &= ~NFC_V1_V2_CONFIG1_INT_MSK;
+ else
+ tmp |= NFC_V1_V2_CONFIG1_INT_MSK;
+
+ writew(tmp, NFC_V1_V2_CONFIG1);
+}
+
+static void irq_control_v3(struct mxc_nand_host *host, int activate)
+{
+ uint32_t tmp;
+
+ tmp = readl(NFC_V3_CONFIG2);
+
+ if (activate)
+ tmp &= ~NFC_V3_CONFIG2_INT_MSK;
+ else
+ tmp |= NFC_V3_CONFIG2_INT_MSK;
+
+ writel(tmp, NFC_V3_CONFIG2);
+}
+
/* This function polls the NANDFC to wait for the basic operation to
* complete by checking the INT bit of config2 register.
*/
@@ -257,10 +306,9 @@ static void wait_op_done(struct mxc_nand_host *host, int useirq)
if (useirq) {
if (!host->check_int(host)) {
-
- enable_irq(host->irq);
-
- wait_event(host->irq_waitq, host->check_int(host));
+ INIT_COMPLETION(host->op_completion);
+ host->irq_control(host, 1);
+ wait_for_completion(&host->op_completion);
}
} else {
while (max_retries-- > 0) {
@@ -731,9 +779,8 @@ static void preset_v1_v2(struct mtd_info *mtd)
struct mxc_nand_host *host = nand_chip->priv;
uint16_t tmp;
- /* enable interrupt, disable spare enable */
+ /* disable spare enable */
tmp = readw(NFC_V1_V2_CONFIG1);
- tmp &= ~NFC_V1_V2_CONFIG1_INT_MSK;
tmp &= ~NFC_V1_V2_CONFIG1_SP_EN;
if (nand_chip->ecc.mode == NAND_ECC_HW) {
tmp |= NFC_V1_V2_CONFIG1_ECC_EN;
@@ -1020,6 +1067,10 @@ static int __init mxcnd_probe(struct platform_device *pdev)
host->send_read_id = send_read_id_v1_v2;
host->get_dev_status = get_dev_status_v1_v2;
host->check_int = check_int_v1_v2;
+ if (cpu_is_mx21())
+ host->irq_control = irq_control_mx21;
+ else
+ host->irq_control = irq_control_v1_v2;
}
if (nfc_is_v21()) {
@@ -1058,6 +1109,7 @@ static int __init mxcnd_probe(struct platform_device *pdev)
host->send_read_id = send_read_id_v3;
host->check_int = check_int_v3;
host->get_dev_status = get_dev_status_v3;
+ host->irq_control = irq_control_v3;
oob_smallpage = &nandv2_hw_eccoob_smallpage;
oob_largepage = &nandv2_hw_eccoob_largepage;
} else
@@ -1089,14 +1141,34 @@ static int __init mxcnd_probe(struct platform_device *pdev)
this->options |= NAND_USE_FLASH_BBT;
}
- init_waitqueue_head(&host->irq_waitq);
+ init_completion(&host->op_completion);
host->irq = platform_get_irq(pdev, 0);
+ /*
+ * mask the interrupt. For i.MX21 explicitely call
+ * irq_control_v1_v2 to use the mask bit. We can't call
+ * disable_irq_nosync() for an interrupt we do not own yet.
+ */
+ if (cpu_is_mx21())
+ irq_control_v1_v2(host, 0);
+ else
+ host->irq_control(host, 0);
+
err = request_irq(host->irq, mxc_nfc_irq, IRQF_DISABLED, DRIVER_NAME, host);
if (err)
goto eirq;
+ host->irq_control(host, 0);
+
+ /*
+ * Now that the interrupt is disabled make sure the interrupt
+ * mask bit is cleared on i.MX21. Otherwise we can't read
+ * the interrupt status bit on this machine.
+ */
+ if (cpu_is_mx21())
+ irq_control_v1_v2(host, 1);
+
/* first scan to find the device and get the page size */
if (nand_scan_ident(mtd, 1, NULL)) {
err = -ENXIO;