1 // SPDX-License-Identifier: GPL-2.0
7    This is a straight-forward UIO driver, where interrupts are disabled
8    by the interrupt handler and re-enabled via a write to the UIO device
9    by the userspace-part.
13    userspace-part could directly modify the Interrupt Enable Register
18    Race conditions exist if the userspace-part directly modifies the
21    this reason, the userspace-part should only directly modify the
23    The userspace-part can safely disable interrupts at any time using
55 	void __iomem *ier0 = info->mem[3].internal_addr + IER0_OFFSET;  in sercos3_disable_interrupts()
58 	priv->ier0_cache |= ioread32(ier0);  in sercos3_disable_interrupts()
68 	void __iomem *ier0 = info->mem[3].internal_addr + IER0_OFFSET;  in sercos3_enable_interrupts()
71 	iowrite32(ioread32(ier0) | priv->ier0_cache, ier0);  in sercos3_enable_interrupts()
72 	priv->ier0_cache = 0;  in sercos3_enable_interrupts()
77 	struct sercos3_priv *priv = info->priv;  in sercos3_handler()
78 	void __iomem *isr0 = info->mem[3].internal_addr + ISR0_OFFSET;  in sercos3_handler()
79 	void __iomem *ier0 = info->mem[3].internal_addr + IER0_OFFSET;  in sercos3_handler()
84 	spin_lock(&priv->ier0_cache_lock);  in sercos3_handler()
86 	spin_unlock(&priv->ier0_cache_lock);  in sercos3_handler()
93 	struct sercos3_priv *priv = info->priv;  in sercos3_irqcontrol()
95 	spin_lock_irq(&priv->ier0_cache_lock);  in sercos3_irqcontrol()
100 	spin_unlock_irq(&priv->ier0_cache_lock);  in sercos3_irqcontrol()
108 	info->mem[n].addr = pci_resource_start(dev, pci_bar);  in sercos3_setup_iomem()
109 	if (!info->mem[n].addr)  in sercos3_setup_iomem()
110 		return -1;  in sercos3_setup_iomem()
111 	info->mem[n].internal_addr = ioremap(pci_resource_start(dev, pci_bar),  in sercos3_setup_iomem()
113 	if (!info->mem[n].internal_addr)  in sercos3_setup_iomem()
114 		return -1;  in sercos3_setup_iomem()
115 	info->mem[n].size = pci_resource_len(dev, pci_bar);  in sercos3_setup_iomem()
116 	info->mem[n].memtype = UIO_MEM_PHYS;  in sercos3_setup_iomem()
127 	info = devm_kzalloc(&dev->dev, sizeof(struct uio_info), GFP_KERNEL);  in sercos3_pci_probe()
129 		return -ENOMEM;  in sercos3_pci_probe()
131 	priv = devm_kzalloc(&dev->dev, sizeof(struct sercos3_priv), GFP_KERNEL);  in sercos3_pci_probe()
133 		return -ENOMEM;  in sercos3_pci_probe()
136 		return -ENODEV;  in sercos3_pci_probe()
153 	spin_lock_init(&priv->ier0_cache_lock);  in sercos3_pci_probe()
154 	info->priv = priv;  in sercos3_pci_probe()
155 	info->name = "Sercos_III_PCI";  in sercos3_pci_probe()
156 	info->version = "0.0.1";  in sercos3_pci_probe()
157 	info->irq = dev->irq;  in sercos3_pci_probe()
158 	info->irq_flags = IRQF_SHARED;  in sercos3_pci_probe()
159 	info->handler = sercos3_handler;  in sercos3_pci_probe()
160 	info->irqcontrol = sercos3_irqcontrol;  in sercos3_pci_probe()
164 	if (uio_register_device(&dev->dev, info))  in sercos3_pci_probe()
171 		if (info->mem[i].internal_addr)  in sercos3_pci_probe()
172 			iounmap(info->mem[i].internal_addr);  in sercos3_pci_probe()
177 	return -ENODEV;  in sercos3_pci_probe()
189 		if (info->mem[i].internal_addr)  in sercos3_pci_remove()
190 			iounmap(info->mem[i].internal_addr);  in sercos3_pci_remove()