spi: aspeed: Improve handling of shared SPI

Merge series from Chin-Ting Kuo <chin-ting_kuo@aspeedtech.com>:

This patch series improves handling of SPI controllers that are
shared by spi-mem devices and other SPI peripherals.

The primary goal of this series is to support non-spi-mem devices in
the ASPEED FMC/SPI controller driver. It also addresses an issue in
the spi-mem framework observed when different types of SPI devices
operate concurrently on the same controller, ensuring that spi-mem
operations are properly serialized.

3 files changed, 32 insertions, 4 deletions

diff --git a/drivers/comedi/comedi_fops.c b/drivers/comedi/comedi_fops.c
index 657c98cd723e..2c3eb9e89571 100644
--- a/drivers/comedi/comedi_fops.c
+++ b/drivers/comedi/comedi_fops.c
@@ -1155,7 +1155,7 @@ static int do_chaninfo_ioctl(struct comedi_device *dev,
 		for (i = 0; i < s->n_chan; i++) {
 			int x;
 
-			x = (dev->minor << 28) | (it->subdev << 24) | (i << 16) |
+			x = (it->subdev << 24) | (i << 16) |
 			    (s->range_table_list[i]->length);
 			if (put_user(x, it->rangelist + i))
 				return -EFAULT;
diff --git a/drivers/comedi/drivers/dmm32at.c b/drivers/comedi/drivers/dmm32at.c
index 644e3b643c79..910cd24b1bed 100644
--- a/drivers/comedi/drivers/dmm32at.c
+++ b/drivers/comedi/drivers/dmm32at.c
@@ -330,6 +330,7 @@ static int dmm32at_ai_cmdtest(struct comedi_device *dev,
 
 static void dmm32at_setaitimer(struct comedi_device *dev, unsigned int nansec)
 {
+	unsigned long irq_flags;
 	unsigned char lo1, lo2, hi2;
 	unsigned short both2;
 
@@ -342,6 +343,9 @@ static void dmm32at_setaitimer(struct comedi_device *dev, unsigned int nansec)
 	/* set counter clocks to 10MHz, disable all aux dio */
 	outb(0, dev->iobase + DMM32AT_CTRDIO_CFG_REG);
 
+	/* serialize access to control register and paged registers */
+	spin_lock_irqsave(&dev->spinlock, irq_flags);
+
 	/* get access to the clock regs */
 	outb(DMM32AT_CTRL_PAGE_8254, dev->iobase + DMM32AT_CTRL_REG);
 
@@ -354,6 +358,8 @@ static void dmm32at_setaitimer(struct comedi_device *dev, unsigned int nansec)
 	outb(lo2, dev->iobase + DMM32AT_CLK2);
 	outb(hi2, dev->iobase + DMM32AT_CLK2);
 
+	spin_unlock_irqrestore(&dev->spinlock, irq_flags);
+
 	/* enable the ai conversion interrupt and the clock to start scans */
 	outb(DMM32AT_INTCLK_ADINT |
 	     DMM32AT_INTCLK_CLKEN | DMM32AT_INTCLK_CLKSEL,
@@ -363,13 +369,19 @@ static void dmm32at_setaitimer(struct comedi_device *dev, unsigned int nansec)
 static int dmm32at_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
 {
 	struct comedi_cmd *cmd = &s->async->cmd;
+	unsigned long irq_flags;
 	int ret;
 
 	dmm32at_ai_set_chanspec(dev, s, cmd->chanlist[0], cmd->chanlist_len);
 
+	/* serialize access to control register and paged registers */
+	spin_lock_irqsave(&dev->spinlock, irq_flags);
+
 	/* reset the interrupt just in case */
 	outb(DMM32AT_CTRL_INTRST, dev->iobase + DMM32AT_CTRL_REG);
 
+	spin_unlock_irqrestore(&dev->spinlock, irq_flags);
+
 	/*
 	 * wait for circuit to settle
 	 * we don't have the 'insn' here but it's not needed
@@ -429,8 +441,13 @@ static irqreturn_t dmm32at_isr(int irq, void *d)
 		comedi_handle_events(dev, s);
 	}
 
+	/* serialize access to control register and paged registers */
+	spin_lock(&dev->spinlock);
+
 	/* reset the interrupt */
 	outb(DMM32AT_CTRL_INTRST, dev->iobase + DMM32AT_CTRL_REG);
+
+	spin_unlock(&dev->spinlock);
 	return IRQ_HANDLED;
 }
 
@@ -481,14 +498,25 @@ static int dmm32at_ao_insn_write(struct comedi_device *dev,
 static int dmm32at_8255_io(struct comedi_device *dev,
 			   int dir, int port, int data, unsigned long regbase)
 {
+	unsigned long irq_flags;
+	int ret;
+
+	/* serialize access to control register and paged registers */
+	spin_lock_irqsave(&dev->spinlock, irq_flags);
+
 	/* get access to the DIO regs */
 	outb(DMM32AT_CTRL_PAGE_8255, dev->iobase + DMM32AT_CTRL_REG);
 
 	if (dir) {
 		outb(data, dev->iobase + regbase + port);
-		return 0;
+		ret = 0;
+	} else {
+		ret = inb(dev->iobase + regbase + port);
 	}
-	return inb(dev->iobase + regbase + port);
+
+	spin_unlock_irqrestore(&dev->spinlock, irq_flags);
+
+	return ret;
 }
 
 /* Make sure the board is there and put it to a known state */
diff --git a/drivers/comedi/range.c b/drivers/comedi/range.c
index 8f43cf88d784..5b8f662365e3 100644
--- a/drivers/comedi/range.c
+++ b/drivers/comedi/range.c
@@ -52,7 +52,7 @@ int do_rangeinfo_ioctl(struct comedi_device *dev,
 	const struct comedi_lrange *lr;
 	struct comedi_subdevice *s;
 
-	subd = (it->range_type >> 24) & 0xf;
+	subd = (it->range_type >> 24) & 0xff;
 	chan = (it->range_type >> 16) & 0xff;
 
 	if (!dev->attached)