Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 1149 insertions, 0 deletions

diff --git a/drivers/gpu/drm/tiny/repaper.c b/drivers/gpu/drm/tiny/repaper.c
new file mode 100644
index 000000000..c2677d081
--- /dev/null
+++ b/drivers/gpu/drm/tiny/repaper.c
@@ -0,0 +1,1149 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * DRM driver for Pervasive Displays RePaper branded e-ink panels
+ *
+ * Copyright 2013-2017 Pervasive Displays, Inc.
+ * Copyright 2017 Noralf Trønnes
+ *
+ * The driver supports:
+ * Material Film: Aurora Mb (V231)
+ * Driver IC: G2 (eTC)
+ *
+ * The controller code was taken from the userspace driver:
+ * https://github.com/repaper/gratis
+ */
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/sched/clock.h>
+#include <linux/spi/spi.h>
+#include <linux/thermal.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_connector.h>
+#include <drm/drm_damage_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fb_dma_helper.h>
+#include <drm/drm_fbdev_generic.h>
+#include <drm/drm_format_helper.h>
+#include <drm/drm_framebuffer.h>
+#include <drm/drm_gem_atomic_helper.h>
+#include <drm/drm_gem_dma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_managed.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_rect.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+
+#define REPAPER_RID_G2_COG_ID	0x12
+
+enum repaper_model {
+	/* 0 is reserved to avoid clashing with NULL */
+	E1144CS021 = 1,
+	E1190CS021,
+	E2200CS021,
+	E2271CS021,
+};
+
+enum repaper_stage {         /* Image pixel -> Display pixel */
+	REPAPER_COMPENSATE,  /* B -> W, W -> B (Current Image) */
+	REPAPER_WHITE,       /* B -> N, W -> W (Current Image) */
+	REPAPER_INVERSE,     /* B -> N, W -> B (New Image) */
+	REPAPER_NORMAL       /* B -> B, W -> W (New Image) */
+};
+
+enum repaper_epd_border_byte {
+	REPAPER_BORDER_BYTE_NONE,
+	REPAPER_BORDER_BYTE_ZERO,
+	REPAPER_BORDER_BYTE_SET,
+};
+
+struct repaper_epd {
+	struct drm_device drm;
+	struct drm_simple_display_pipe pipe;
+	const struct drm_display_mode *mode;
+	struct drm_connector connector;
+	struct spi_device *spi;
+
+	struct gpio_desc *panel_on;
+	struct gpio_desc *border;
+	struct gpio_desc *discharge;
+	struct gpio_desc *reset;
+	struct gpio_desc *busy;
+
+	struct thermal_zone_device *thermal;
+
+	unsigned int height;
+	unsigned int width;
+	unsigned int bytes_per_scan;
+	const u8 *channel_select;
+	unsigned int stage_time;
+	unsigned int factored_stage_time;
+	bool middle_scan;
+	bool pre_border_byte;
+	enum repaper_epd_border_byte border_byte;
+
+	u8 *line_buffer;
+	void *current_frame;
+
+	bool cleared;
+	bool partial;
+};
+
+static inline struct repaper_epd *drm_to_epd(struct drm_device *drm)
+{
+	return container_of(drm, struct repaper_epd, drm);
+}
+
+static int repaper_spi_transfer(struct spi_device *spi, u8 header,
+				const void *tx, void *rx, size_t len)
+{
+	void *txbuf = NULL, *rxbuf = NULL;
+	struct spi_transfer tr[2] = {};
+	u8 *headerbuf;
+	int ret;
+
+	headerbuf = kmalloc(1, GFP_KERNEL);
+	if (!headerbuf)
+		return -ENOMEM;
+
+	headerbuf[0] = header;
+	tr[0].tx_buf = headerbuf;
+	tr[0].len = 1;
+
+	/* Stack allocated tx? */
+	if (tx && len <= 32) {
+		txbuf = kmemdup(tx, len, GFP_KERNEL);
+		if (!txbuf) {
+			ret = -ENOMEM;
+			goto out_free;
+		}
+	}
+
+	if (rx) {
+		rxbuf = kmalloc(len, GFP_KERNEL);
+		if (!rxbuf) {
+			ret = -ENOMEM;
+			goto out_free;
+		}
+	}
+
+	tr[1].tx_buf = txbuf ? txbuf : tx;
+	tr[1].rx_buf = rxbuf;
+	tr[1].len = len;
+
+	ndelay(80);
+	ret = spi_sync_transfer(spi, tr, 2);
+	if (rx && !ret)
+		memcpy(rx, rxbuf, len);
+
+out_free:
+	kfree(headerbuf);
+	kfree(txbuf);
+	kfree(rxbuf);
+
+	return ret;
+}
+
+static int repaper_write_buf(struct spi_device *spi, u8 reg,
+			     const u8 *buf, size_t len)
+{
+	int ret;
+
+	ret = repaper_spi_transfer(spi, 0x70, &reg, NULL, 1);
+	if (ret)
+		return ret;
+
+	return repaper_spi_transfer(spi, 0x72, buf, NULL, len);
+}
+
+static int repaper_write_val(struct spi_device *spi, u8 reg, u8 val)
+{
+	return repaper_write_buf(spi, reg, &val, 1);
+}
+
+static int repaper_read_val(struct spi_device *spi, u8 reg)
+{
+	int ret;
+	u8 val;
+
+	ret = repaper_spi_transfer(spi, 0x70, &reg, NULL, 1);
+	if (ret)
+		return ret;
+
+	ret = repaper_spi_transfer(spi, 0x73, NULL, &val, 1);
+
+	return ret ? ret : val;
+}
+
+static int repaper_read_id(struct spi_device *spi)
+{
+	int ret;
+	u8 id;
+
+	ret = repaper_spi_transfer(spi, 0x71, NULL, &id, 1);
+
+	return ret ? ret : id;
+}
+
+static void repaper_spi_mosi_low(struct spi_device *spi)
+{
+	const u8 buf[1] = { 0 };
+
+	spi_write(spi, buf, 1);
+}
+
+/* pixels on display are numbered from 1 so even is actually bits 1,3,5,... */
+static void repaper_even_pixels(struct repaper_epd *epd, u8 **pp,
+				const u8 *data, u8 fixed_value, const u8 *mask,
+				enum repaper_stage stage)
+{
+	unsigned int b;
+
+	for (b = 0; b < (epd->width / 8); b++) {
+		if (data) {
+			u8 pixels = data[b] & 0xaa;
+			u8 pixel_mask = 0xff;
+			u8 p1, p2, p3, p4;
+
+			if (mask) {
+				pixel_mask = (mask[b] ^ pixels) & 0xaa;
+				pixel_mask |= pixel_mask >> 1;
+			}
+
+			switch (stage) {
+			case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */
+				pixels = 0xaa | ((pixels ^ 0xaa) >> 1);
+				break;
+			case REPAPER_WHITE:      /* B -> N, W -> W (Current) */
+				pixels = 0x55 + ((pixels ^ 0xaa) >> 1);
+				break;
+			case REPAPER_INVERSE:    /* B -> N, W -> B (New) */
+				pixels = 0x55 | (pixels ^ 0xaa);
+				break;
+			case REPAPER_NORMAL:     /* B -> B, W -> W (New) */
+				pixels = 0xaa | (pixels >> 1);
+				break;
+			}
+
+			pixels = (pixels & pixel_mask) | (~pixel_mask & 0x55);
+			p1 = (pixels >> 6) & 0x03;
+			p2 = (pixels >> 4) & 0x03;
+			p3 = (pixels >> 2) & 0x03;
+			p4 = (pixels >> 0) & 0x03;
+			pixels = (p1 << 0) | (p2 << 2) | (p3 << 4) | (p4 << 6);
+			*(*pp)++ = pixels;
+		} else {
+			*(*pp)++ = fixed_value;
+		}
+	}
+}
+
+/* pixels on display are numbered from 1 so odd is actually bits 0,2,4,... */
+static void repaper_odd_pixels(struct repaper_epd *epd, u8 **pp,
+			       const u8 *data, u8 fixed_value, const u8 *mask,
+			       enum repaper_stage stage)
+{
+	unsigned int b;
+
+	for (b = epd->width / 8; b > 0; b--) {
+		if (data) {
+			u8 pixels = data[b - 1] & 0x55;
+			u8 pixel_mask = 0xff;
+
+			if (mask) {
+				pixel_mask = (mask[b - 1] ^ pixels) & 0x55;
+				pixel_mask |= pixel_mask << 1;
+			}
+
+			switch (stage) {
+			case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */
+				pixels = 0xaa | (pixels ^ 0x55);
+				break;
+			case REPAPER_WHITE:      /* B -> N, W -> W (Current) */
+				pixels = 0x55 + (pixels ^ 0x55);
+				break;
+			case REPAPER_INVERSE:    /* B -> N, W -> B (New) */
+				pixels = 0x55 | ((pixels ^ 0x55) << 1);
+				break;
+			case REPAPER_NORMAL:     /* B -> B, W -> W (New) */
+				pixels = 0xaa | pixels;
+				break;
+			}
+
+			pixels = (pixels & pixel_mask) | (~pixel_mask & 0x55);
+			*(*pp)++ = pixels;
+		} else {
+			*(*pp)++ = fixed_value;
+		}
+	}
+}
+
+/* interleave bits: (byte)76543210 -> (16 bit).7.6.5.4.3.2.1 */
+static inline u16 repaper_interleave_bits(u16 value)
+{
+	value = (value | (value << 4)) & 0x0f0f;
+	value = (value | (value << 2)) & 0x3333;
+	value = (value | (value << 1)) & 0x5555;
+
+	return value;
+}
+
+/* pixels on display are numbered from 1 */
+static void repaper_all_pixels(struct repaper_epd *epd, u8 **pp,
+			       const u8 *data, u8 fixed_value, const u8 *mask,
+			       enum repaper_stage stage)
+{
+	unsigned int b;
+
+	for (b = epd->width / 8; b > 0; b--) {
+		if (data) {
+			u16 pixels = repaper_interleave_bits(data[b - 1]);
+			u16 pixel_mask = 0xffff;
+
+			if (mask) {
+				pixel_mask = repaper_interleave_bits(mask[b - 1]);
+
+				pixel_mask = (pixel_mask ^ pixels) & 0x5555;
+				pixel_mask |= pixel_mask << 1;
+			}
+
+			switch (stage) {
+			case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */
+				pixels = 0xaaaa | (pixels ^ 0x5555);
+				break;
+			case REPAPER_WHITE:      /* B -> N, W -> W (Current) */
+				pixels = 0x5555 + (pixels ^ 0x5555);
+				break;
+			case REPAPER_INVERSE:    /* B -> N, W -> B (New) */
+				pixels = 0x5555 | ((pixels ^ 0x5555) << 1);
+				break;
+			case REPAPER_NORMAL:     /* B -> B, W -> W (New) */
+				pixels = 0xaaaa | pixels;
+				break;
+			}
+
+			pixels = (pixels & pixel_mask) | (~pixel_mask & 0x5555);
+			*(*pp)++ = pixels >> 8;
+			*(*pp)++ = pixels;
+		} else {
+			*(*pp)++ = fixed_value;
+			*(*pp)++ = fixed_value;
+		}
+	}
+}
+
+/* output one line of scan and data bytes to the display */
+static void repaper_one_line(struct repaper_epd *epd, unsigned int line,
+			     const u8 *data, u8 fixed_value, const u8 *mask,
+			     enum repaper_stage stage)
+{
+	u8 *p = epd->line_buffer;
+	unsigned int b;
+
+	repaper_spi_mosi_low(epd->spi);
+
+	if (epd->pre_border_byte)
+		*p++ = 0x00;
+
+	if (epd->middle_scan) {
+		/* data bytes */
+		repaper_odd_pixels(epd, &p, data, fixed_value, mask, stage);
+
+		/* scan line */
+		for (b = epd->bytes_per_scan; b > 0; b--) {
+			if (line / 4 == b - 1)
+				*p++ = 0x03 << (2 * (line & 0x03));
+			else
+				*p++ = 0x00;
+		}
+
+		/* data bytes */
+		repaper_even_pixels(epd, &p, data, fixed_value, mask, stage);
+	} else {
+		/*
+		 * even scan line, but as lines on display are numbered from 1,
+		 * line: 1,3,5,...
+		 */
+		for (b = 0; b < epd->bytes_per_scan; b++) {
+			if (0 != (line & 0x01) && line / 8 == b)
+				*p++ = 0xc0 >> (line & 0x06);
+			else
+				*p++ = 0x00;
+		}
+
+		/* data bytes */
+		repaper_all_pixels(epd, &p, data, fixed_value, mask, stage);
+
+		/*
+		 * odd scan line, but as lines on display are numbered from 1,
+		 * line: 0,2,4,6,...
+		 */
+		for (b = epd->bytes_per_scan; b > 0; b--) {
+			if (0 == (line & 0x01) && line / 8 == b - 1)
+				*p++ = 0x03 << (line & 0x06);
+			else
+				*p++ = 0x00;
+		}
+	}
+
+	switch (epd->border_byte) {
+	case REPAPER_BORDER_BYTE_NONE:
+		break;
+
+	case REPAPER_BORDER_BYTE_ZERO:
+		*p++ = 0x00;
+		break;
+
+	case REPAPER_BORDER_BYTE_SET:
+		switch (stage) {
+		case REPAPER_COMPENSATE:
+		case REPAPER_WHITE:
+		case REPAPER_INVERSE:
+			*p++ = 0x00;
+			break;
+		case REPAPER_NORMAL:
+			*p++ = 0xaa;
+			break;
+		}
+		break;
+	}
+
+	repaper_write_buf(epd->spi, 0x0a, epd->line_buffer,
+			  p - epd->line_buffer);
+
+	/* Output data to panel */
+	repaper_write_val(epd->spi, 0x02, 0x07);
+
+	repaper_spi_mosi_low(epd->spi);
+}
+
+static void repaper_frame_fixed(struct repaper_epd *epd, u8 fixed_value,
+				enum repaper_stage stage)
+{
+	unsigned int line;
+
+	for (line = 0; line < epd->height; line++)
+		repaper_one_line(epd, line, NULL, fixed_value, NULL, stage);
+}
+
+static void repaper_frame_data(struct repaper_epd *epd, const u8 *image,
+			       const u8 *mask, enum repaper_stage stage)
+{
+	unsigned int line;
+
+	if (!mask) {
+		for (line = 0; line < epd->height; line++) {
+			repaper_one_line(epd, line,
+					 &image[line * (epd->width / 8)],
+					 0, NULL, stage);
+		}
+	} else {
+		for (line = 0; line < epd->height; line++) {
+			size_t n = line * epd->width / 8;
+
+			repaper_one_line(epd, line, &image[n], 0, &mask[n],
+					 stage);
+		}
+	}
+}
+
+static void repaper_frame_fixed_repeat(struct repaper_epd *epd, u8 fixed_value,
+				       enum repaper_stage stage)
+{
+	u64 start = local_clock();
+	u64 end = start + (epd->factored_stage_time * 1000 * 1000);
+
+	do {
+		repaper_frame_fixed(epd, fixed_value, stage);
+	} while (local_clock() < end);
+}
+
+static void repaper_frame_data_repeat(struct repaper_epd *epd, const u8 *image,
+				      const u8 *mask, enum repaper_stage stage)
+{
+	u64 start = local_clock();
+	u64 end = start + (epd->factored_stage_time * 1000 * 1000);
+
+	do {
+		repaper_frame_data(epd, image, mask, stage);
+	} while (local_clock() < end);
+}
+
+static void repaper_get_temperature(struct repaper_epd *epd)
+{
+	int ret, temperature = 0;
+	unsigned int factor10x;
+
+	if (!epd->thermal)
+		return;
+
+	ret = thermal_zone_get_temp(epd->thermal, &temperature);
+	if (ret) {
+		DRM_DEV_ERROR(&epd->spi->dev, "Failed to get temperature (%d)\n", ret);
+		return;
+	}
+
+	temperature /= 1000;
+
+	if (temperature <= -10)
+		factor10x = 170;
+	else if (temperature <= -5)
+		factor10x = 120;
+	else if (temperature <= 5)
+		factor10x = 80;
+	else if (temperature <= 10)
+		factor10x = 40;
+	else if (temperature <= 15)
+		factor10x = 30;
+	else if (temperature <= 20)
+		factor10x = 20;
+	else if (temperature <= 40)
+		factor10x = 10;
+	else
+		factor10x = 7;
+
+	epd->factored_stage_time = epd->stage_time * factor10x / 10;
+}
+
+static int repaper_fb_dirty(struct drm_framebuffer *fb)
+{
+	struct drm_gem_dma_object *dma_obj = drm_fb_dma_get_gem_obj(fb, 0);
+	struct repaper_epd *epd = drm_to_epd(fb->dev);
+	unsigned int dst_pitch = 0;
+	struct iosys_map dst, vmap;
+	struct drm_rect clip;
+	int idx, ret = 0;
+	u8 *buf = NULL;
+
+	if (!drm_dev_enter(fb->dev, &idx))
+		return -ENODEV;
+
+	/* repaper can't do partial updates */
+	clip.x1 = 0;
+	clip.x2 = fb->width;
+	clip.y1 = 0;
+	clip.y2 = fb->height;
+
+	repaper_get_temperature(epd);
+
+	DRM_DEBUG("Flushing [FB:%d] st=%ums\n", fb->base.id,
+		  epd->factored_stage_time);
+
+	buf = kmalloc_array(fb->width, fb->height, GFP_KERNEL);
+	if (!buf) {
+		ret = -ENOMEM;
+		goto out_exit;
+	}
+
+	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
+	if (ret)
+		goto out_free;
+
+	iosys_map_set_vaddr(&dst, buf);
+	iosys_map_set_vaddr(&vmap, dma_obj->vaddr);
+	drm_fb_xrgb8888_to_mono(&dst, &dst_pitch, &vmap, fb, &clip);
+
+	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
+
+	if (epd->partial) {
+		repaper_frame_data_repeat(epd, buf, epd->current_frame,
+					  REPAPER_NORMAL);
+	} else if (epd->cleared) {
+		repaper_frame_data_repeat(epd, epd->current_frame, NULL,
+					  REPAPER_COMPENSATE);
+		repaper_frame_data_repeat(epd, epd->current_frame, NULL,
+					  REPAPER_WHITE);
+		repaper_frame_data_repeat(epd, buf, NULL, REPAPER_INVERSE);
+		repaper_frame_data_repeat(epd, buf, NULL, REPAPER_NORMAL);
+
+		epd->partial = true;
+	} else {
+		/* Clear display (anything -> white) */
+		repaper_frame_fixed_repeat(epd, 0xff, REPAPER_COMPENSATE);
+		repaper_frame_fixed_repeat(epd, 0xff, REPAPER_WHITE);
+		repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_INVERSE);
+		repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_NORMAL);
+
+		/* Assuming a clear (white) screen output an image */
+		repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_COMPENSATE);
+		repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_WHITE);
+		repaper_frame_data_repeat(epd, buf, NULL, REPAPER_INVERSE);
+		repaper_frame_data_repeat(epd, buf, NULL, REPAPER_NORMAL);
+
+		epd->cleared = true;
+		epd->partial = true;
+	}
+
+	memcpy(epd->current_frame, buf, fb->width * fb->height / 8);
+
+	/*
+	 * An extra frame write is needed if pixels are set in the bottom line,
+	 * or else grey lines rises up from the pixels
+	 */
+	if (epd->pre_border_byte) {
+		unsigned int x;
+
+		for (x = 0; x < (fb->width / 8); x++)
+			if (buf[x + (fb->width * (fb->height - 1) / 8)]) {
+				repaper_frame_data_repeat(epd, buf,
+							  epd->current_frame,
+							  REPAPER_NORMAL);
+				break;
+			}
+	}
+
+out_free:
+	kfree(buf);
+out_exit:
+	drm_dev_exit(idx);
+
+	return ret;
+}
+
+static void power_off(struct repaper_epd *epd)
+{
+	/* Turn off power and all signals */
+	gpiod_set_value_cansleep(epd->reset, 0);
+	gpiod_set_value_cansleep(epd->panel_on, 0);
+	if (epd->border)
+		gpiod_set_value_cansleep(epd->border, 0);
+
+	/* Ensure SPI MOSI and CLOCK are Low before CS Low */
+	repaper_spi_mosi_low(epd->spi);
+
+	/* Discharge pulse */
+	gpiod_set_value_cansleep(epd->discharge, 1);
+	msleep(150);
+	gpiod_set_value_cansleep(epd->discharge, 0);
+}
+
+static enum drm_mode_status repaper_pipe_mode_valid(struct drm_simple_display_pipe *pipe,
+						    const struct drm_display_mode *mode)
+{
+	struct drm_crtc *crtc = &pipe->crtc;
+	struct repaper_epd *epd = drm_to_epd(crtc->dev);
+
+	return drm_crtc_helper_mode_valid_fixed(crtc, mode, epd->mode);
+}
+
+static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe,
+				struct drm_crtc_state *crtc_state,
+				struct drm_plane_state *plane_state)
+{
+	struct repaper_epd *epd = drm_to_epd(pipe->crtc.dev);
+	struct spi_device *spi = epd->spi;
+	struct device *dev = &spi->dev;
+	bool dc_ok = false;
+	int i, ret, idx;
+
+	if (!drm_dev_enter(pipe->crtc.dev, &idx))
+		return;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Power up sequence */
+	gpiod_set_value_cansleep(epd->reset, 0);
+	gpiod_set_value_cansleep(epd->panel_on, 0);
+	gpiod_set_value_cansleep(epd->discharge, 0);
+	if (epd->border)
+		gpiod_set_value_cansleep(epd->border, 0);
+	repaper_spi_mosi_low(spi);
+	usleep_range(5000, 10000);
+
+	gpiod_set_value_cansleep(epd->panel_on, 1);
+	/*
+	 * This delay comes from the repaper.org userspace driver, it's not
+	 * mentioned in the datasheet.
+	 */
+	usleep_range(10000, 15000);
+	gpiod_set_value_cansleep(epd->reset, 1);
+	if (epd->border)
+		gpiod_set_value_cansleep(epd->border, 1);
+	usleep_range(5000, 10000);
+	gpiod_set_value_cansleep(epd->reset, 0);
+	usleep_range(5000, 10000);
+	gpiod_set_value_cansleep(epd->reset, 1);
+	usleep_range(5000, 10000);
+
+	/* Wait for COG to become ready */
+	for (i = 100; i > 0; i--) {
+		if (!gpiod_get_value_cansleep(epd->busy))
+			break;
+
+		usleep_range(10, 100);
+	}
+
+	if (!i) {
+		DRM_DEV_ERROR(dev, "timeout waiting for panel to become ready.\n");
+		power_off(epd);
+		goto out_exit;
+	}
+
+	repaper_read_id(spi);
+	ret = repaper_read_id(spi);
+	if (ret != REPAPER_RID_G2_COG_ID) {
+		if (ret < 0)
+			dev_err(dev, "failed to read chip (%d)\n", ret);
+		else
+			dev_err(dev, "wrong COG ID 0x%02x\n", ret);
+		power_off(epd);
+		goto out_exit;
+	}
+
+	/* Disable OE */
+	repaper_write_val(spi, 0x02, 0x40);
+
+	ret = repaper_read_val(spi, 0x0f);
+	if (ret < 0 || !(ret & 0x80)) {
+		if (ret < 0)
+			DRM_DEV_ERROR(dev, "failed to read chip (%d)\n", ret);
+		else
+			DRM_DEV_ERROR(dev, "panel is reported broken\n");
+		power_off(epd);
+		goto out_exit;
+	}
+
+	/* Power saving mode */
+	repaper_write_val(spi, 0x0b, 0x02);
+	/* Channel select */
+	repaper_write_buf(spi, 0x01, epd->channel_select, 8);
+	/* High power mode osc */
+	repaper_write_val(spi, 0x07, 0xd1);
+	/* Power setting */
+	repaper_write_val(spi, 0x08, 0x02);
+	/* Vcom level */
+	repaper_write_val(spi, 0x09, 0xc2);
+	/* Power setting */
+	repaper_write_val(spi, 0x04, 0x03);
+	/* Driver latch on */
+	repaper_write_val(spi, 0x03, 0x01);
+	/* Driver latch off */
+	repaper_write_val(spi, 0x03, 0x00);
+	usleep_range(5000, 10000);
+
+	/* Start chargepump */
+	for (i = 0; i < 4; ++i) {
+		/* Charge pump positive voltage on - VGH/VDL on */
+		repaper_write_val(spi, 0x05, 0x01);
+		msleep(240);
+
+		/* Charge pump negative voltage on - VGL/VDL on */
+		repaper_write_val(spi, 0x05, 0x03);
+		msleep(40);
+
+		/* Charge pump Vcom on - Vcom driver on */
+		repaper_write_val(spi, 0x05, 0x0f);
+		msleep(40);
+
+		/* check DC/DC */
+		ret = repaper_read_val(spi, 0x0f);
+		if (ret < 0) {
+			DRM_DEV_ERROR(dev, "failed to read chip (%d)\n", ret);
+			power_off(epd);
+			goto out_exit;
+		}
+
+		if (ret & 0x40) {
+			dc_ok = true;
+			break;
+		}
+	}
+
+	if (!dc_ok) {
+		DRM_DEV_ERROR(dev, "dc/dc failed\n");
+		power_off(epd);
+		goto out_exit;
+	}
+
+	/*
+	 * Output enable to disable
+	 * The userspace driver sets this to 0x04, but the datasheet says 0x06
+	 */
+	repaper_write_val(spi, 0x02, 0x04);
+
+	epd->partial = false;
+out_exit:
+	drm_dev_exit(idx);
+}
+
+static void repaper_pipe_disable(struct drm_simple_display_pipe *pipe)
+{
+	struct repaper_epd *epd = drm_to_epd(pipe->crtc.dev);
+	struct spi_device *spi = epd->spi;
+	unsigned int line;
+
+	/*
+	 * This callback is not protected by drm_dev_enter/exit since we want to
+	 * turn off the display on regular driver unload. It's highly unlikely
+	 * that the underlying SPI controller is gone should this be called after
+	 * unplug.
+	 */
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Nothing frame */
+	for (line = 0; line < epd->height; line++)
+		repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL,
+				 REPAPER_COMPENSATE);
+
+	/* 2.7" */
+	if (epd->border) {
+		/* Dummy line */
+		repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL,
+				 REPAPER_COMPENSATE);
+		msleep(25);
+		gpiod_set_value_cansleep(epd->border, 0);
+		msleep(200);
+		gpiod_set_value_cansleep(epd->border, 1);
+	} else {
+		/* Border dummy line */
+		repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL,
+				 REPAPER_NORMAL);
+		msleep(200);
+	}
+
+	/* not described in datasheet */
+	repaper_write_val(spi, 0x0b, 0x00);
+	/* Latch reset turn on */
+	repaper_write_val(spi, 0x03, 0x01);
+	/* Power off charge pump Vcom */
+	repaper_write_val(spi, 0x05, 0x03);
+	/* Power off charge pump neg voltage */
+	repaper_write_val(spi, 0x05, 0x01);
+	msleep(120);
+	/* Discharge internal */
+	repaper_write_val(spi, 0x04, 0x80);
+	/* turn off all charge pumps */
+	repaper_write_val(spi, 0x05, 0x00);
+	/* Turn off osc */
+	repaper_write_val(spi, 0x07, 0x01);
+	msleep(50);
+
+	power_off(epd);
+}
+
+static void repaper_pipe_update(struct drm_simple_display_pipe *pipe,
+				struct drm_plane_state *old_state)
+{
+	struct drm_plane_state *state = pipe->plane.state;
+	struct drm_rect rect;
+
+	if (!pipe->crtc.state->active)
+		return;
+
+	if (drm_atomic_helper_damage_merged(old_state, state, &rect))
+		repaper_fb_dirty(state->fb);
+}
+
+static const struct drm_simple_display_pipe_funcs repaper_pipe_funcs = {
+	.mode_valid = repaper_pipe_mode_valid,
+	.enable = repaper_pipe_enable,
+	.disable = repaper_pipe_disable,
+	.update = repaper_pipe_update,
+};
+
+static int repaper_connector_get_modes(struct drm_connector *connector)
+{
+	struct repaper_epd *epd = drm_to_epd(connector->dev);
+
+	return drm_connector_helper_get_modes_fixed(connector, epd->mode);
+}
+
+static const struct drm_connector_helper_funcs repaper_connector_hfuncs = {
+	.get_modes = repaper_connector_get_modes,
+};
+
+static const struct drm_connector_funcs repaper_connector_funcs = {
+	.reset = drm_atomic_helper_connector_reset,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.destroy = drm_connector_cleanup,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static const struct drm_mode_config_funcs repaper_mode_config_funcs = {
+	.fb_create = drm_gem_fb_create_with_dirty,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = drm_atomic_helper_commit,
+};
+
+static const uint32_t repaper_formats[] = {
+	DRM_FORMAT_XRGB8888,
+};
+
+static const struct drm_display_mode repaper_e1144cs021_mode = {
+	DRM_SIMPLE_MODE(128, 96, 29, 22),
+};
+
+static const u8 repaper_e1144cs021_cs[] = { 0x00, 0x00, 0x00, 0x00,
+					    0x00, 0x0f, 0xff, 0x00 };
+
+static const struct drm_display_mode repaper_e1190cs021_mode = {
+	DRM_SIMPLE_MODE(144, 128, 36, 32),
+};
+
+static const u8 repaper_e1190cs021_cs[] = { 0x00, 0x00, 0x00, 0x03,
+					    0xfc, 0x00, 0x00, 0xff };
+
+static const struct drm_display_mode repaper_e2200cs021_mode = {
+	DRM_SIMPLE_MODE(200, 96, 46, 22),
+};
+
+static const u8 repaper_e2200cs021_cs[] = { 0x00, 0x00, 0x00, 0x00,
+					    0x01, 0xff, 0xe0, 0x00 };
+
+static const struct drm_display_mode repaper_e2271cs021_mode = {
+	DRM_SIMPLE_MODE(264, 176, 57, 38),
+};
+
+static const u8 repaper_e2271cs021_cs[] = { 0x00, 0x00, 0x00, 0x7f,
+					    0xff, 0xfe, 0x00, 0x00 };
+
+DEFINE_DRM_GEM_DMA_FOPS(repaper_fops);
+
+static const struct drm_driver repaper_driver = {
+	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
+	.fops			= &repaper_fops,
+	DRM_GEM_DMA_DRIVER_OPS_VMAP,
+	.name			= "repaper",
+	.desc			= "Pervasive Displays RePaper e-ink panels",
+	.date			= "20170405",
+	.major			= 1,
+	.minor			= 0,
+};
+
+static const struct of_device_id repaper_of_match[] = {
+	{ .compatible = "pervasive,e1144cs021", .data = (void *)E1144CS021 },
+	{ .compatible = "pervasive,e1190cs021", .data = (void *)E1190CS021 },
+	{ .compatible = "pervasive,e2200cs021", .data = (void *)E2200CS021 },
+	{ .compatible = "pervasive,e2271cs021", .data = (void *)E2271CS021 },
+	{},
+};
+MODULE_DEVICE_TABLE(of, repaper_of_match);
+
+static const struct spi_device_id repaper_id[] = {
+	{ "e1144cs021", E1144CS021 },
+	{ "e1190cs021", E1190CS021 },
+	{ "e2200cs021", E2200CS021 },
+	{ "e2271cs021", E2271CS021 },
+	{ },
+};
+MODULE_DEVICE_TABLE(spi, repaper_id);
+
+static int repaper_probe(struct spi_device *spi)
+{
+	const struct drm_display_mode *mode;
+	const struct spi_device_id *spi_id;
+	struct device *dev = &spi->dev;
+	enum repaper_model model;
+	const char *thermal_zone;
+	struct repaper_epd *epd;
+	size_t line_buffer_size;
+	struct drm_device *drm;
+	const void *match;
+	int ret;
+
+	match = device_get_match_data(dev);
+	if (match) {
+		model = (enum repaper_model)match;
+	} else {
+		spi_id = spi_get_device_id(spi);
+		model = (enum repaper_model)spi_id->driver_data;
+	}
+
+	/* The SPI device is used to allocate dma memory */
+	if (!dev->coherent_dma_mask) {
+		ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
+		if (ret) {
+			dev_warn(dev, "Failed to set dma mask %d\n", ret);
+			return ret;
+		}
+	}
+
+	epd = devm_drm_dev_alloc(dev, &repaper_driver,
+				 struct repaper_epd, drm);
+	if (IS_ERR(epd))
+		return PTR_ERR(epd);
+
+	drm = &epd->drm;
+
+	ret = drmm_mode_config_init(drm);
+	if (ret)
+		return ret;
+	drm->mode_config.funcs = &repaper_mode_config_funcs;
+
+	epd->spi = spi;
+
+	epd->panel_on = devm_gpiod_get(dev, "panel-on", GPIOD_OUT_LOW);
+	if (IS_ERR(epd->panel_on)) {
+		ret = PTR_ERR(epd->panel_on);
+		if (ret != -EPROBE_DEFER)
+			DRM_DEV_ERROR(dev, "Failed to get gpio 'panel-on'\n");
+		return ret;
+	}
+
+	epd->discharge = devm_gpiod_get(dev, "discharge", GPIOD_OUT_LOW);
+	if (IS_ERR(epd->discharge)) {
+		ret = PTR_ERR(epd->discharge);
+		if (ret != -EPROBE_DEFER)
+			DRM_DEV_ERROR(dev, "Failed to get gpio 'discharge'\n");
+		return ret;
+	}
+
+	epd->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(epd->reset)) {
+		ret = PTR_ERR(epd->reset);
+		if (ret != -EPROBE_DEFER)
+			DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
+		return ret;
+	}
+
+	epd->busy = devm_gpiod_get(dev, "busy", GPIOD_IN);
+	if (IS_ERR(epd->busy)) {
+		ret = PTR_ERR(epd->busy);
+		if (ret != -EPROBE_DEFER)
+			DRM_DEV_ERROR(dev, "Failed to get gpio 'busy'\n");
+		return ret;
+	}
+
+	if (!device_property_read_string(dev, "pervasive,thermal-zone",
+					 &thermal_zone)) {
+		epd->thermal = thermal_zone_get_zone_by_name(thermal_zone);
+		if (IS_ERR(epd->thermal)) {
+			DRM_DEV_ERROR(dev, "Failed to get thermal zone: %s\n", thermal_zone);
+			return PTR_ERR(epd->thermal);
+		}
+	}
+
+	switch (model) {
+	case E1144CS021:
+		mode = &repaper_e1144cs021_mode;
+		epd->channel_select = repaper_e1144cs021_cs;
+		epd->stage_time = 480;
+		epd->bytes_per_scan = 96 / 4;
+		epd->middle_scan = true; /* data-scan-data */
+		epd->pre_border_byte = false;
+		epd->border_byte = REPAPER_BORDER_BYTE_ZERO;
+		break;
+
+	case E1190CS021:
+		mode = &repaper_e1190cs021_mode;
+		epd->channel_select = repaper_e1190cs021_cs;
+		epd->stage_time = 480;
+		epd->bytes_per_scan = 128 / 4 / 2;
+		epd->middle_scan = false; /* scan-data-scan */
+		epd->pre_border_byte = false;
+		epd->border_byte = REPAPER_BORDER_BYTE_SET;
+		break;
+
+	case E2200CS021:
+		mode = &repaper_e2200cs021_mode;
+		epd->channel_select = repaper_e2200cs021_cs;
+		epd->stage_time = 480;
+		epd->bytes_per_scan = 96 / 4;
+		epd->middle_scan = true; /* data-scan-data */
+		epd->pre_border_byte = true;
+		epd->border_byte = REPAPER_BORDER_BYTE_NONE;
+		break;
+
+	case E2271CS021:
+		epd->border = devm_gpiod_get(dev, "border", GPIOD_OUT_LOW);
+		if (IS_ERR(epd->border)) {
+			ret = PTR_ERR(epd->border);
+			if (ret != -EPROBE_DEFER)
+				DRM_DEV_ERROR(dev, "Failed to get gpio 'border'\n");
+			return ret;
+		}
+
+		mode = &repaper_e2271cs021_mode;
+		epd->channel_select = repaper_e2271cs021_cs;
+		epd->stage_time = 630;
+		epd->bytes_per_scan = 176 / 4;
+		epd->middle_scan = true; /* data-scan-data */
+		epd->pre_border_byte = true;
+		epd->border_byte = REPAPER_BORDER_BYTE_NONE;
+		break;
+
+	default:
+		return -ENODEV;
+	}
+
+	epd->mode = mode;
+	epd->width = mode->hdisplay;
+	epd->height = mode->vdisplay;
+	epd->factored_stage_time = epd->stage_time;
+
+	line_buffer_size = 2 * epd->width / 8 + epd->bytes_per_scan + 2;
+	epd->line_buffer = devm_kzalloc(dev, line_buffer_size, GFP_KERNEL);
+	if (!epd->line_buffer)
+		return -ENOMEM;
+
+	epd->current_frame = devm_kzalloc(dev, epd->width * epd->height / 8,
+					  GFP_KERNEL);
+	if (!epd->current_frame)
+		return -ENOMEM;
+
+	drm->mode_config.min_width = mode->hdisplay;
+	drm->mode_config.max_width = mode->hdisplay;
+	drm->mode_config.min_height = mode->vdisplay;
+	drm->mode_config.max_height = mode->vdisplay;
+
+	drm_connector_helper_add(&epd->connector, &repaper_connector_hfuncs);
+	ret = drm_connector_init(drm, &epd->connector, &repaper_connector_funcs,
+				 DRM_MODE_CONNECTOR_SPI);
+	if (ret)
+		return ret;
+
+	ret = drm_simple_display_pipe_init(drm, &epd->pipe, &repaper_pipe_funcs,
+					   repaper_formats, ARRAY_SIZE(repaper_formats),
+					   NULL, &epd->connector);
+	if (ret)
+		return ret;
+
+	drm_mode_config_reset(drm);
+
+	ret = drm_dev_register(drm, 0);
+	if (ret)
+		return ret;
+
+	spi_set_drvdata(spi, drm);
+
+	DRM_DEBUG_DRIVER("SPI speed: %uMHz\n", spi->max_speed_hz / 1000000);
+
+	drm_fbdev_generic_setup(drm, 0);
+
+	return 0;
+}
+
+static void repaper_remove(struct spi_device *spi)
+{
+	struct drm_device *drm = spi_get_drvdata(spi);
+
+	drm_dev_unplug(drm);
+	drm_atomic_helper_shutdown(drm);
+}
+
+static void repaper_shutdown(struct spi_device *spi)
+{
+	drm_atomic_helper_shutdown(spi_get_drvdata(spi));
+}
+
+static struct spi_driver repaper_spi_driver = {
+	.driver = {
+		.name = "repaper",
+		.of_match_table = repaper_of_match,
+	},
+	.id_table = repaper_id,
+	.probe = repaper_probe,
+	.remove = repaper_remove,
+	.shutdown = repaper_shutdown,
+};
+module_spi_driver(repaper_spi_driver);
+
+MODULE_DESCRIPTION("Pervasive Displays RePaper DRM driver");
+MODULE_AUTHOR("Noralf Trønnes");
+MODULE_LICENSE("GPL");